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A117271 Column 0 of triangle A117270, which is the matrix log of triangle A117269. 3
0, 1, 2, 12, 134, 2100, 42302, 1041852, 30331814, 1019056260, 38805685262, 1651676734092, 77703508288694, 4003868870257620, 224255353667365022, 13565588100060643932, 881405810330856632774, 61218510507062012550180 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..17.

FORMULA

E.g.f.: A(x) = log( (3-sqrt(5-4*exp(x)))/2 ).

a(n) ~ sqrt(10) * n^(n-1) / (6 * exp(n) * (log(5)-2*log(2))^(n-1/2)). - Vaclav Kotesovec, Feb 25 2014

PROG

(PARI) {a(n)=local(C=matrix(n+1, n+1, r, c, if(r>=c, binomial(r-1, c-1))), M=C, L); for(i=1, n+1, M=(M-M^0)^2+C); L=sum(r=1, #M, -(M^0-M)^r/r); return(L[n+1, 1])}

CROSSREFS

Cf. A117269, A117270.

Sequence in context: A080487 A077696 A326361 * A289998 A180353 A208873

Adjacent sequences:  A117268 A117269 A117270 * A117272 A117273 A117274

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 05 2006

STATUS

approved

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Last modified September 19 13:13 EDT 2020. Contains 337178 sequences. (Running on oeis4.)