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A138748
a(n) = (n+(n+1)) + (n*(n+1)) + (n^(n+1)).
1
1, 6, 19, 100, 1053, 15666, 279991, 5764872, 134217817, 3486784510, 100000000131, 3138428376876, 106993205379253, 3937376385699498, 155568095557812463, 6568408355712890896, 295147905179352826161, 14063084452067724991350, 708235345355337676358011, 37589973457545958193356020, 2097152000000000000000000461
OFFSET
0,2
COMMENTS
Sum of three arithmetic operations (sum, product, powers) of two consecutive integers.
FORMULA
a(n) = A028387(n) + A007778(n). - R. J. Mathar, Apr 03 2008
EXAMPLE
a(0) = (0+1) + (0*1) + (0^1) = 1;
a(1) = (1+2) + (1*2) + (1^2) = 6;
a(2) = (2+3) + (2*3) + (2^3) = 19; etc.
MAPLE
A028387 := proc(n) n+(n+1)^2 ; end: A007778 := proc(n) n^(n+1) ; end: A138748 := proc(n) A028387(n)+A007778(n) ; end: seq(A138748(n), n=0..20) ; # R. J. Mathar, Apr 03 2008
MATHEMATICA
Table[2n+1+n(n+1)+n^(n+1), {n, 0, 20}] (* Harvey P. Dale, Sep 13 2024 *)
CROSSREFS
Sequence in context: A355539 A323686 A285853 * A097899 A223505 A054236
KEYWORD
easy,nonn
AUTHOR
EXTENSIONS
More terms from R. J. Mathar, Apr 03 2008
STATUS
approved