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A152551
a(n) = (2*n+1)^floor((n-1)/2).
5
1, 1, 1, 7, 9, 121, 169, 3375, 4913, 130321, 194481, 6436343, 9765625, 387420489, 594823321, 27512614111, 42618442977, 2251875390625, 3512479453921, 208728361158759, 327381934393961, 21611482313284249, 34050628916015625
OFFSET
0,4
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
FORMULA
a(n) = Sum_{k=0..n(n-1)/2} A152550(n,k)*(-1)^k.
MATHEMATICA
Table[(2n+1)^Floor[(n-1)/2], {n, 0, 30}] (* Harvey P. Dale, Nov 21 2011 *)
PROG
(PARI) a(n)=(2*n+1)^((n-1)\2)
(Magma) [(2*n+1)^Floor((n-1)/2): n in [0..50]]; // G. C. Greubel, Nov 16 2017
CROSSREFS
Cf. A152550, A152552 (q=2), A152553 (q=3).
Sequence in context: A137058 A116237 A123746 * A012252 A262538 A306184
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 07 2008
STATUS
approved