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A152554 Largest term in row n of triangle A152550. 1
1, 1, 3, 16, 180, 2640, 52934, 1307556, 39067428, 1369499060, 54995284784, 2507211396061, 127388480252917, 7144814127814222, 439553511977812220, 29347225935730588372, 2116793087420823777580, 164035715631344596393196 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Compare to row sums of triangle A152550: (2n+1)^(n-1).

Triangle A152550 lists coefficients in a q-analog of the function [LambertW(-2x)/(-2x)]^(1/2).

LINKS

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

PROG

(PARI) {a(n)=local(e_q=1+sum(j=1, n, x^j/prod(i=1, j, (q^i-1)/(q-1))), LW2_q=sqrt(serreverse(x/(e_q+x*O(x^n))^2)/x)); vecsort(Vec(polcoeff(LW2_q+x*O(x^n), n, x)*prod(i=1, n, (q^i-1)/(q-1))))[n*(n-1)/2+1]}

CROSSREFS

Cf. A152550, A152551 (q=-1), A152552 (q=2), A152553 (q=3).

Sequence in context: A203593 A304902 A024041 * A254430 A180721 A192668

Adjacent sequences:  A152551 A152552 A152553 * A152555 A152556 A152557

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Dec 07 2008

STATUS

approved

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Last modified August 11 00:32 EDT 2020. Contains 336403 sequences. (Running on oeis4.)