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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
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
Sequence in context: A080487 A077696 A326361 * A289998 A180353 A208873
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Mar 05 2006
STATUS
approved

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Last modified June 7 21:29 EDT 2023. Contains 363157 sequences. (Running on oeis4.)