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A118403 Unsigned row sums of triangle A118401; a(n) = A118402(n^2-n+2), where A118402 is the row sums of triangle A118400. 3
1, 1, 3, 5, 9, 15, 23, 33, 45, 59, 75, 93, 113, 135, 159, 185, 213, 243, 275, 309, 345, 383, 423, 465, 509, 555, 603, 653, 705, 759, 815, 873, 933, 995, 1059, 1125, 1193, 1263, 1335, 1409, 1485, 1563, 1643, 1725, 1809, 1895, 1983, 2073, 2165, 2259, 2355 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Muniru A Asiru, Table of n, a(n) for n = 0..10000

FORMULA

G.f.: A(x) = (1-2*x+2*x^2)*(1+x^2)/(1-x)^3.

a(n) = A027688(n-2) for n > 1. - Jon Maiga, Jan 02 2019

MAPLE

seq(coeff(series((1-2*x+2*x^2)*(1+x^2)/(1-x)^3, x, n+1), x, n), n = 0 .. 55); # Muniru A Asiru, Jan 02 2019

MATHEMATICA

Join[{1, 1}, Table[n^2 + n + 3, {n, 0, 47}]] (* Jon Maiga, Jan 02 2019 *)

PROG

(PARI) {a(n)=polcoeff((1-2*x+2*x^2)*(1+x^2)/(1-x+x*O(x^n))^3, n, x)}

CROSSREFS

Cf. A027688, A118401, A118402.

Sequence in context: A022940 A025207 A027688 * A033498 A147493 A178961

Adjacent sequences:  A118400 A118401 A118402 * A118404 A118405 A118406

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Apr 27 2006

STATUS

approved

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Last modified October 17 14:47 EDT 2019. Contains 328114 sequences. (Running on oeis4.)