18256

Appears in sequences

• Sinh(x) / cos(x) = Sum_{n>=0} a(n)*x^(2n+1)/(2n+1)!.at n=4A002084
• Expansion of e.g.f. exp(x)/cos(x).at n=9A003701
• Theta series of odd 8-dimensional 5-modular lattice O(5).at n=30A029719
• Trajectory of 3 under map n->15n+1 if n odd, n->n/2 if n even.at n=12A037105
• Boustrophedon transform of n mod 2.at n=9A062161
• Numbers k such that phi((prime(k)-1)/2) = sigma(k).at n=42A068474
• Triangle T(n,k) read by rows, where e.g.f. for T(n,k) is exp((1+y)*x)/(1-x).at n=39A073107
• Number of permutations of 1..n containing the relative rank sequence { 241653 } at any spacing.at n=3A159153
• Number of (n+2) X 3 binary arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.at n=15A190025
• Monotonic ordering of set S generated by these rules: if x and y are in S then x^2+y^2-xy is in S, and 2 is in S.at n=21A192533
• Positive integers n such that (n+84)^3 - n^3 is a square.at n=4A263949
• Expansion of (1 + x)^2 / ((1 - x)^2*(1 + 2*x + 2*x^2)^2).at n=24A322040
• Expansion of e.g.f. (1 + sinh(x)) / cos(x).at n=9A336024
• a(n) = (n!/6) * Sum_{k=0..n-3} 1/k!.at n=8A357479
• a(n) = Sum_{k=1..n} (-1)^(k-1) * binomial(k+3,4) * floor(n/k).at n=28A366939
• Triangle read by rows: T(n, k) = e * binomial(n, k) * Gamma(k + 1, 1).at n=41A371686
• E.g.f. (exp(x) - 1)/cos(x).at n=8A380053
• Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of e.g.f. B(x)^k, where B(x) is the e.g.f. of A384689.at n=40A384690