50544

Appears in sequences

• n is equal to the number of 2's in all numbers <= n written in base 6.at n=14A014891
• Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite AFO = AlPO4-41 [Al20P20O80] starting with a T4 atom.at n=6A018956
• McKay-Thompson series of class 30B for the Monster group with a(0) = 0.at n=43A058613
• Numbers k such that the number of primes <= k is phi(phi(k)).at n=24A063999
• 30 'Reverse and Add' steps are needed to reach a palindrome.at n=31A065319
• Number of strings of length n over Z_6 with trace 0 and subtrace 2.at n=7A073973
• Number of strings of length n over Z_6 with trace 2 and subtrace 0.at n=7A073983
• Numbers with prime factorization pq^4r^5.at n=9A190468
• a(n) = 9*a(n-1) - 3*a(n-2), with a(0)=0, a(1)=1.at n=6A190980
• Square array read by antidiagonals downwards: super Patalan numbers of order 3.at n=29A248324
• a(0) = 3; a(n+1) is the smallest number not in the sequence such that a(n+1) - Sum_{i=1..n} a(i) divides a(n+1) - Product_{i=1..n} a(i).at n=22A254344
• Smallest k such that A261029(k) = n.at n=30A260935
• Expansion of a(q)^2 * (c(q)/3)^3 in powers of q where a(), c() are cubic AGM theta functions.at n=14A266288
• Expansion of Product_{k=1..16} theta_3(q^k), where theta_3() is the Jacobi theta function.at n=38A320247
• Numbers with an even number of prime factors (counted with multiplicity) that can be factored into squarefree semiprimes (A320911) but cannot be factored into distinct semiprimes (A320892).at n=18A320893
• a(n) = T(n, 3), where T(n, k) = Sum_{i=0..n} i^k * binomial(n, i) * (1/2)^(n-k).at n=36A366151