20156

Appears in sequences

• q-Fibonacci numbers for q=5, scaling a(n-2).at n=6A015462
• (n! - n)/2 for even n.at n=3A016101
• Positive numbers k such that k and 3*k are anagrams in base 8 (written in base 8).at n=10A023074
• Numbers n such that (sigma(n-2)+sigma(n+2))/2 = sigma(n).at n=38A099631
• a(n+3) = 2a(n+2) - 3a(n+1) + 2a(n); a(0) = 1, a(1) = 3, a(2) = 4.at n=28A105579
• Expansion of x^2*(-3+4*x)/(1-x^3+x^4).at n=59A110061
• Number of 4-step one space at a time bishop's tours on an n X n board summed over all starting positions.at n=25A187157
• Number of nondecreasing arrangements of n+2 numbers in 0..8 with the last equal to 8 and each after the second equal to the sum of one or two of the preceding three.at n=36A190040
• a(n) is the number of terms in the expansion of (x-y)*(x^4-y^4)*(x^9-y^9)*...*(x^(n^2)-y^(n^2)).at n=38A225549
• Triangle T(n,k) giving the largest member of "the infinite trunk of factorial beanstalk" (A219666) whose factorial base representation contains n digits (A084558) and the most significant such digit (A099563) is k.at n=23A230429
• Lengths of runs of the initial digits of semiprimes in decimal representation, cf. A239634.at n=46A239639
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 587", based on the 5-celled von Neumann neighborhood.at n=27A273079
• Number of integer partitions whose sum plus co-rank is n, where co-rank is maximum of length and largest part.at n=51A325193
• Expansion of Sum_{k>0} x^(2*k)/(1 - k*x^k)^2.at n=34A363641