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A022282
a(n) = n*(25*n - 1)/2.
3
0, 12, 49, 111, 198, 310, 447, 609, 796, 1008, 1245, 1507, 1794, 2106, 2443, 2805, 3192, 3604, 4041, 4503, 4990, 5502, 6039, 6601, 7188, 7800, 8437, 9099, 9786, 10498, 11235, 11997, 12784, 13596, 14433
OFFSET
0,2
FORMULA
a(n) = 25*n + a(n-1) - 13 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
G.f.: x*(12 + 13*x)/(1 - x)^3 . - R. J. Mathar, Aug 04 2016
a(n) = A000217(13*n-1) - A000217(12*n-1). - Bruno Berselli, Oct 14 2016
E.g.f.: (x/2)*(25*x + 24)*exp(x). - G. C. Greubel, Aug 23 2017
a(n) = 3*a(n-1)-3*a(n-2)+a(n-3). - Wesley Ivan Hurt, Apr 23 2021
MATHEMATICA
Table[n (25 n - 1)/2, {n, 0, 40}] (* Bruno Berselli, Oct 14 2016 *)
PROG
(PARI) a(n)=n*(25*n-1)/2 \\ Charles R Greathouse IV, Jun 16 2017
(Magma) [n*(25*n - 1)/2 : n in [0..50]]; // Wesley Ivan Hurt, Apr 23 2021
CROSSREFS
Cf. A022283.
Cf. similar sequences listed in A022288.
Sequence in context: A376185 A077612 A041272 * A009959 A009950 A252178
KEYWORD
nonn,easy
STATUS
approved