|
Search: id:A152559
|
|
| |
|
| 1, 2, 7, 42, 495, 7436, 153361, 3853322, 116503839, 4127612326, 167061660005, 7671346786170, 392298901133895, 22113791358359574, 1365967717507556804, 91549507266620360316, 6624242349107514460269, 514871138228210665592112
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Compare to row sums of triangle A152555: 2*(2n+2)^(n-1).
Triangle A152555 lists coefficients in a q-analogue of the function LambertW(-2x)/(-2x).
|
|
PROGRAM
|
(PARI) {a(n)=local(e_q=1+sum(j=1, n, x^j/prod(i=1, j, (q^i-1)/(q-1))), LW2_q=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. A152555, A152556(q=-1), A152557 (q=2) A152558 (q=3).
Sequence in context: A005130 A091669 A108042 this_sequence A001174 A067975 A065298
Adjacent sequences: A152556 A152557 A152558 this_sequence A152560 A152561 A152562
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Paul D. Hanna (pauldhanna(AT)juno.com), Dec 07 2008
|
|
|
Search completed in 0.002 seconds
|
