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A022281
a(n) = n*(23*n + 1)/2.
4
0, 12, 47, 105, 186, 290, 417, 567, 740, 936, 1155, 1397, 1662, 1950, 2261, 2595, 2952, 3332, 3735, 4161, 4610, 5082, 5577, 6095, 6636, 7200, 7787, 8397, 9030, 9686, 10365, 11067, 11792, 12540, 13311
OFFSET
0,2
FORMULA
a(n) = 23*n + a(n-1) - 11 for n>0, a(0)=0. - Vincenzo Librandi, Aug 04 2010
G.f.: x*(12 + 11*x)/(1 - x)^3 . - R. J. Mathar, Aug 04 2016
a(n) = A000217(12*n) - A000217(11*n). - Bruno Berselli, Oct 13 2016
E.g.f.: (x/2)*(23*x + 24)*exp(x). - G. C. Greubel, Aug 23 2017
MATHEMATICA
Table[n (23 n + 1)/2, {n, 0, 40}] (* or *) LinearRecurrence[{3, -3, 1}, {0, 12, 47}, 40] (* Harvey P. Dale, Aug 16 2016 *)
PROG
(PARI) a(n)=n*(23*n+1)/2 \\ Charles R Greathouse IV, Jun 16 2017
CROSSREFS
Cf. similar sequences listed in A022289.
Sequence in context: A200669 A197471 A159013 * A244803 A024183 A051673
KEYWORD
nonn,easy
STATUS
approved