A192735 - OEIS

A192735

Left edge of the triangle in A033291.

1, 2, 6, 16, 30, 54, 91, 136, 198, 280, 374, 492, 637, 798, 990, 1216, 1462, 1746, 2071, 2420, 2814, 3256, 3726, 4248, 4825, 5434, 6102, 6832, 7598, 8430, 9331, 10272, 11286, 12376, 13510, 14724, 16021, 17366, 18798, 20320, 21894, 23562, 25327, 27148, 29070

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OFFSET

1,2

COMMENTS

a(n) = A087483(n-2) * n.

LINKS

Table of n, a(n) for n=1..45.

Index entries for linear recurrences with constant coefficients, signature (2,-1,2,-4,2,-1,2,-1).

FORMULA

G.f.: x*(x^2+1)*(2*x^4+4*x^3+2*x^2+1) / ((x-1)^4*(x^2+x+1)^2). - Colin Barker, Mar 31 2013

MAPLE

A192735 := proc(n)