28968

Appears in sequences

• Number of 2n-bead black-white reversible complementable necklaces with n black beads.at n=12A006840
• arcsin(sinh(x)+sin(x))=2*x+8/3!*x^3+290/5!*x^5+28968/7!*x^7...at n=3A013027
• a(n) = T(n,m) + T(n,m+1) + ... + T(n,n), m=[ (n+1)/2 ], T given by A026747.at n=14A026869
• a(n) = 25*n^2 + 2*n.at n=33A154377
• a(n) = 1728*n - 408.at n=16A157266
• Numbers k such that A(k+1) = A(k) + 1, where A() = A005101() are the abundant numbers.at n=33A169822
• Central terms of the triangle in A074911.at n=6A225621
• Number of (n+1) X (4+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=6A235013
• Number of (n+1) X (7+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 3, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=3A235016
• a(n) = [x^n] 2 / (1 + x*(2*x + 3) + sqrt((x + 1)*(1 - 3*x))). Alternating row sums of A379907.at n=15A379824