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A118393 Eigenvector of triangle A059344. E.g.f.: exp( Sum_{n>=0} x^(2^n) ). 1
1, 1, 3, 7, 49, 201, 1411, 7183, 108417, 816049, 9966691, 80843511, 1381416433, 14049020857, 216003063459, 2309595457471, 72927332784001, 1046829280528353, 23403341433961027, 329565129021010279, 9695176730057249841 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

E.g.f. of A059344 is: exp(x+y*x^2). More generally, given a triangle with e.g.f.: exp(x+y*x^b), the eigenvector will have e.g.f.: exp( Sum_{n>=0} x^(b^n) ).

FORMULA

a(n) = Sum_{k=0..[n/2]} n!/k!/(n-2*k)! *a(k) for n>=0, with a(0)=1.

PROG

(PARI) a(n)=n!*polcoeff(exp(sum(k=0, #binary(n), x^(2^k))+x*O(x^n)), n)

CROSSREFS

Cf. A059344, variants: A118395, A118930.

Sequence in context: A077559 A062959 A190444 * A113775 A113236 A035499

Adjacent sequences:  A118390 A118391 A118392 * A118394 A118395 A118396

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), May 07 2006

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.