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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, 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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified August 3 22:03 EDT 2021. Contains 346441 sequences. (Running on oeis4.)