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A102296
a(n) = (1/6)*(n+1)*(10*n^2 + 17*n + 12).
1
2, 13, 43, 102, 200, 347, 553, 828, 1182, 1625, 2167, 2818, 3588, 4487, 5525, 6712, 8058, 9573, 11267, 13150, 15232, 17523, 20033, 22772, 25750, 28977, 32463, 36218, 40252, 44575, 49197, 54128, 59378, 64957, 70875, 77142, 83768, 90763, 98137
OFFSET
0,1
COMMENTS
A floretion-generated sequence which arises from a particular transform of the centered square numbers: A001844. Specifically, (a(n)) is the jesfor-transform of the sequence A001844 with respect to the floretion given in the program code. The sequence relates centered square numbers, triangular numbers and centered octahedral numbers to (n+1)^3. Note: this was made possible in part by the formula already given for A085786.
Floretion Algebra Multiplication Program, FAMP Code: 4jesforseq[ + .25'j + .25'k + .25j' + .25k' + .25'ij' + .25'ik' + .25'ji' + .25'ki' + e ], vesforseq = A001844, ForType: 1A, LoopType: tes.
FORMULA
G.f.: (x+1)*(3x+2)/(x-1)^4;
a(n) = 2*A001844(n+1)_0 - 2*A001845(n+1)_0 + A085786(n+1)_1 ( "_" denotes offset ) (n+1)^3 = 2*A001845(n+1) - 2*A001844(n+1) - A000217(n+1) - a(n).
MATHEMATICA
LinearRecurrence[{4, -6, 4, -1}, {2, 13, 43, 102}, 50] (* Paolo Xausa, Mar 09 2024 *)
PROG
(Magma) [(1/6)*(n+1)*(10*n^2+17*n+12): n in [0..50]]; // Vincenzo Librandi, May 30 2011
(PARI) a(n) = (n+1)*(10*n^2+17*n+12)/6
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Creighton Dement, Feb 19 2005
STATUS
approved