30,000

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30,000 (thirty thousand) is the natural number that comes after 29,999 and before 30,001.

Selected numbers in the range 30001–39999

30001 to 30999

31000 to 31999

  • 31116 = octahedral number[5]
  • 31185 = number of partitions of 39[6]
  • 31337 = cousin prime, pronounced elite, an alternate way to spell 1337, an obfuscated alphabet made with numbers and punctuation, known and used in the gamer, hacker, and BBS cultures.
  • 31395 = square pyramidal number
  • 31397 = prime number followed by a record prime gap of 72, the first greater than 52[7]
  • 31688 = the number of years approximately equal to 1 trillion seconds
  • 31721 = start of a prime quadruplet[8]
  • 31929 = Zeisel number[9]

32000 to 32999

33000 to 33999

  • 33333 = repdigit
  • 33461 = Pell number,[12] Markov number[13]
  • 33511 = square pyramidal number
  • 33781 = octahedral number[5]

34000 to 34999

  • 34560 = 5 superfactorial[14]
  • 34790 = number of non-isomorphic set-systems of weight 13.
  • 34841 = start of a prime quadruplet[8]
  • 34969 = favorite number of the Muppet character Count von Count[15]

35000 to 35999

36000 to 36999

  • 36100 = sum of the cubes of the first 19 positive integers
  • 36463 – number of parallelogram polyominoes with 14 cells[19]
  • 36594 = octahedral number[5]

37000 to 37999

  • 37338 = number of partitions of 40[6]
  • 37378 = semi-meandric number[20]
  • 37634 = third term of the Lucas–Lehmer sequence
  • 37666 = Markov number[13]
  • 37926 = pentagonal pyramidal number[4]

38000 to 38999

  • 38024 = square pyramidal number
  • 38209 = n such that n | (3n + 5)[21]
  • 38305 = the largest Forges-compatible number (for index 32) to the field (6,14). But a conjecture of Viggo Brun predicts that there are infinitely many such numbers for any Galois field F unless F is bad.
  • 38416 = 144
  • 38501 = 74 + 1902: Friedlander-Iwaniec prime.[22] Smallest prime separated by at least 40 from the nearest primes (38461 and 38543). It is thus an isolated prime.[23] Chen prime.[24]
  • 38807 = number of non-equivalent ways of expressing 10,000,000 as the sum of two prime numbers[25]
  • 38962 = Kaprekar number[26]

39000 to 39999

  • 39299 = Integer connected with coefficients in expansion of Weierstrass P-function[27]
  • 39304 = 343
  • 39559 = octahedral number[5]
  • 39648 = tetranacci number[28]

Primes

There are 958 prime numbers between 30,000 and 40,000.

References

  1. Sloane, N. J. A., ed. "Sequence A002110 (Primorial numbers)". OEIS Foundation. https://oeis.org/A002110. 
  2. 2.0 2.1 Sloane, N. J. A., ed. "Sequence A001599 (Harmonic or Ore numbers)". OEIS Foundation. https://oeis.org/A001599. 
  3. Sloane, N. J. A., ed. "Sequence A007539 (first n-fold perfect (or n-multiperfect) number)". OEIS Foundation. https://oeis.org/A007539. 
  4. 4.0 4.1 4.2 Sloane, N. J. A., ed. "Sequence A002411 (Pentagonal pyramidal numbers)". OEIS Foundation. https://oeis.org/A002411. 
  5. 5.0 5.1 5.2 5.3 Sloane, N. J. A., ed. "Sequence A005900 (Octahedral numbers)". OEIS Foundation. https://oeis.org/A005900. 
  6. 6.0 6.1 Sloane, N. J. A., ed. "Sequence A000041 (a(n) is the number of partitions of n (the partition numbers))". OEIS Foundation. https://oeis.org/A000041. 
  7. Weisstein, Eric W.. "Prime Gaps". http://mathworld.wolfram.com/PrimeGaps.html. 
  8. 8.0 8.1 Sloane, N. J. A., ed. "Sequence A007530 (Prime quadruples: numbers k such that k, k+2, k+6, k+8 are all prime)". OEIS Foundation. https://oeis.org/A007530. 
  9. Sloane, N. J. A., ed. "Sequence A051015 (Zeisel numbers)". OEIS Foundation. https://oeis.org/A051015. 
  10. Sloane, N. J. A., ed. "Sequence A088959 (Lowest numbers which are d-Pythagorean decomposable, i.e., square is expressible as sum of two positive squares in more ways than for any smaller number)". OEIS Foundation. https://oeis.org/A088959. 
  11. Sloane, N. J. A., ed. "Sequence A094133 (Leyland prime numbers)". OEIS Foundation. https://oeis.org/A094133. 
  12. Sloane, N. J. A., ed. "Sequence A000129 (Pell numbers)". OEIS Foundation. https://oeis.org/A000129. 
  13. 13.0 13.1 Sloane, N. J. A., ed. "Sequence A002559 (Markoff (or Markov) numbers)". OEIS Foundation. https://oeis.org/A002559. 
  14. Sloane, N. J. A., ed. "Sequence A000178 (Superfactorials)". OEIS Foundation. https://oeis.org/A000178. 
  15. "Why was 34,969 Count von Count's magic number?". BBC News. 2012-08-30. https://www.bbc.co.uk/news/magazine-19409960. 
  16. Sloane, N. J. A., ed. "Sequence A000073 (Tribonacci numbers)". OEIS Foundation. https://oeis.org/A000073. 
  17. Sloane, N. J. A., ed. "Sequence A005165 (Alternating factorials)". OEIS Foundation. https://oeis.org/A005165. 
  18. Sloane, N. J. A., ed. "Sequence A195163 (1000-gonal numbers)". OEIS Foundation. https://oeis.org/A195163. 
  19. Sloane, N. J. A., ed. "Sequence A006958 (Number of parallelogram polyominoes with n cells (also called staircase polyominoes, although that term is overused))". OEIS Foundation. https://oeis.org/A006958. 
  20. "Sloane's A000682 : Semimeanders". OEIS Foundation. https://oeis.org/A000682. 
  21. Sloane, N. J. A., ed. "Sequence A277288 (Positive integers n such that n | (3^n + 5))". OEIS Foundation. https://oeis.org/A277288. 
  22. Sloane, N. J. A., ed. "Sequence A028916 (Friedlander-Iwaniec primes: Primes of form a^2 + b^4)". OEIS Foundation. https://oeis.org/A028916. 
  23. Sloane, N. J. A., ed. "Sequence A023186 (Lonely (or isolated) primes)". OEIS Foundation. https://oeis.org/A023186. 
  24. Sloane, N. J. A., ed. "Sequence A109611 (Chen primes: primes p such that p + 2 is either a prime or a semiprime)". OEIS Foundation. https://oeis.org/A109611. 
  25. Sloane, N. J. A., ed. "Sequence A065577 (Number of Goldbach partitions of 10^n)". OEIS Foundation. https://oeis.org/A065577. Retrieved 2023-08-31. 
  26. Sloane, N. J. A., ed. "Sequence A006886 (Kaprekar numbers)". OEIS Foundation. https://oeis.org/A006886. 
  27. Sloane, N. J. A., ed. "Sequence A002770 (Weierstrass P-function)". OEIS Foundation. https://oeis.org/A002770. 
  28. Sloane, N. J. A., ed. "Sequence A000078 (Tetranacci numbers)". OEIS Foundation. https://oeis.org/A000078.