cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A143690 a(n) = A007318 * [1, 6, 14, 9, 0, 0, 0, ...].

Original entry on oeis.org

1, 7, 27, 70, 145, 261, 427, 652, 945, 1315, 1771, 2322, 2977, 3745, 4635, 5656, 6817, 8127, 9595, 11230, 13041, 15037, 17227, 19620, 22225, 25051, 28107, 31402, 34945, 38745, 42811, 47152, 51777, 56695, 61915, 67446, 73297, 79477, 85995, 92860, 100081, 107667
Offset: 0

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Author

Gary W. Adamson, Aug 29 2008

Keywords

Comments

Binomial transform of [1, 6, 14, 9, 0, 0, 0,...].
Row sums of triangle A033292.

Examples

			a(3) = 70 = (1, 3, 3, 1) dot (1, 6, 14, 9) = (1 + 18 + 42 + 9). a(3) = 70 = sum of row 3 terms of triangle A033292: (13 + 16 + 19, + 22).
		

Crossrefs

Cf. A226449. - Bruno Berselli, Jun 09 2013

Programs

  • Mathematica
    Table[(n+1)*(3*n^2+2*n+2)/2, {n,0,50}] (* G. C. Greubel, May 30 2021 *)
  • Sage
    [(n+1)*(3*n^2+2*n+2)/2 for n in (0..50)] # G. C. Greubel, May 30 2021

Formula

From R. J. Mathar, Aug 29 2008: (Start)
G.f.: (1 +3*x +5*x^2)/(1-x)^4.
a(n) = A002412(n+1) + 5*A000292(n-1). (End)
a(n) = A000326(n+1) + (n+1)*A000326(n). - Bruno Berselli, Jun 07 2013
From G. C. Greubel, May 30 2021: (Start)
a(n) = (n+1)*(3*n^2 +2*n +2)/2.
E.g.f.: (1/2)*(2 +12*x +14*x^2 +3*x^3)*exp(x). (End)

Extensions

Extended beyond a(14) by R. J. Mathar, Aug 29 2008