A101165 a(n) = (7*n^3 + 6*n^2 + 5*n) / 6.

0, 3, 15, 43, 94, 175, 293, 455, 668, 939, 1275, 1683, 2170, 2743, 3409, 4175, 5048, 6035, 7143, 8379, 9750, 11263, 12925, 14743, 16724, 18875, 21203, 23715, 26418, 29319, 32425, 35743, 39280, 43043, 47039, 51275, 55758, 60495, 65493, 70759

Offset: 0

Author

Reinhard Zumkeller, Dec 03 2004

Keywords

• nonn

Comments

a(n) = A001845(n) - A000292(n+1) = A101164(n+3,3) for n>0.

Crossrefs

Cf. A005449, A101166.

Programs

Magma

[(7*n^3 + 6*n^2 + 5*n) / 6: n in [0..40]]; // Vincenzo Librandi, Dec 26 2010

Formula

From Chai Wah Wu, May 29 2016: (Start)

a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4).

G.f.: x*(x^2 + 3*x + 3)/(x - 1)^4.

(End)