20408

Appears in sequences

• s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = A001950 (upper Wythoff sequence).at n=43A024864
• Numerators of continued fraction convergents to sqrt(193).at n=8A041358
• Numbers whose base-7 representation contains exactly four 3's.at n=31A043408
• Numbers k such that (3^k - 7)/2 is prime.at n=15A063679
• (a(2n+1)+a(2n))^2 = a(2n+1) a(2n) (concatenated, not multiplied).at n=35A112268
• Let X denote the 2 X 2 matrix [0,1; 1,exp(1)], let Y = X^n; a(n) = floor(Y[1,1]).at n=10A138804
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (-1, 0, 1), (1, -1, 1), (1, 1, -1), (1, 1, 0)}.at n=8A149474
• Left part of the square of the n-th Kaprekar number.at n=24A194218
• The number of overpartitions of n into parts congruent to 2, 4, or 5 modulo 6.at n=50A253136
• Number of (n+2)X(4+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001.at n=4A260203
• Number of (n+2) X (5+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001.at n=3A260204
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001.at n=31A260207
• T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000000 00000001 or 00010001.at n=32A260207
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 549", based on the 5-celled von Neumann neighborhood.at n=26A272844
• Number of perfect-power divisors of n!.at n=36A336416
• Number of perfect-power divisors of n!.at n=37A336416