A102814 a(-1) = 1, a(n) = Sum_{k=0..n} A034851(n,k)*a(k-1) where A034851(n,k) are entries in Losanitsch's triangle.

1, 1, 2, 4, 11, 30, 103, 354, 1440, 5911, 27651, 131062, 690543, 3693765, 21585068, 128165652, 820859645, 5343318222, 37155889171, 262577578134, 1967281479508, 14975397597557, 120122032987319, 978625889818014, 8359402026954939, 72495015037575673, 656446920912518700

Offset

-1,3

Links

Andrew Howroyd, Table of n, a(n) for n = -1..200

Prog

(PARI) \\ here T(n, k) is A034851(n, k).
T(n, k) = {(1/2)*(binomial(n, k) + binomial(n%2, k%2) * binomial(n\2, k\2))}
seq(n)={my(a=vector(n+1)); a[1]=1; for(n=1, n, a[n+1]=sum(k=1, n, a[k]*T(n-1, k-1))); a} \\ Andrew Howroyd, Nov 06 2019

Crossrefs

Cf. A034851.

Sequence in context: A148158 A148159 A275310 * A193059 A034770 A276687

Adjacent sequences: A102811 A102812 A102813 * A102815 A102816 A102817

Keyword

nonn

Author

Gerald McGarvey, Feb 26 2005

Extensions

Terms a(12) and beyond from Andrew Howroyd, Nov 06 2019

Status

approved