22158

Appears in sequences

• a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 5, starting 1,0,1,1.at n=14A025273
• G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^2 * x^k/(1-x)^k ).at n=12A217333
• Number of partitions p = [x(1), ..., x(k)], where x(1) >= x(2) >= ... >= x(k), of n such that max(x(i) - x(i-1)) is a part of p.at n=43A241735
• Number of (n+1) X (6+1) 0..1 arrays with every 2 X 2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically.at n=16A253395
• Numbers n such that for some m, A166133(m)=n, A166133(m+1)=n^2-1, in order of increasing m.at n=36A256406
• Numbers n such that for some m, A166133(m)=n, A166133(m+1)=n^2-1, in increasing order.at n=37A256407
• Numbers k such that k^7 - 1 and k^7 + 1 are semiprimes.at n=5A279272
• Number of valid hook configurations of permutations of [n] that avoid the patterns 231 and 321.at n=13A307788
• Matula-Goebel tree number of tree n with a new leaf added below each existing vertex.at n=43A348067