30969

Appears in sequences

• Number of primes <= n!.at n=9A003604
• Numbers whose set of base-13 digits is {1,3}.at n=33A032920
• Numbers k such that 2*5^k - 3 is prime.at n=21A057915
• Divisors of 10^15 - 1.at n=34A111117
• a(n) is the smallest positive number such that a(n)*n is an anagram of a(n)*9.at n=22A175698
• a(n) is the smallest k > 0 such that the first n multiples of k have the same sum of digits, but (n+1)k has a different one. a(n)=0 if no such k exists.at n=39A238088
• Expansion of the series reversion of Sum_{k>=1} x^(k*(k+1)/2).at n=16A291418
• Number of compositions of n into parts with distinct multiplicities and with exactly nine parts.at n=23A321779
• Number of 3-dimensional tilings of a 2 X 2 X n box using 2 X 2 X 1 plates and 1 X 2 X 1 dominos.at n=6A359884