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A109815
n^2 followed by n^3 followed by n.
0
1, 1, 1, 4, 8, 2, 9, 27, 3, 16, 64, 4, 25, 125, 5, 36, 216, 6, 49, 343, 7, 64, 512, 8, 81, 729, 9, 100, 1000, 10, 121, 1331, 11, 144, 1728, 12, 169, 2197, 13, 196, 2744, 14, 225, 3375, 15, 256, 4096, 16, 289, 4913, 17, 324, 5832, 18, 361, 6859, 19, 400, 8000, 20
OFFSET
1,4
FORMULA
G.f.: x*(1+x+x^2+4*x^4-2*x^5-x^6+x^7+x^8) / ( (x-1)^4*(1+x+x^2)^4 ). - R. J. Mathar, Mar 03 2014
a(n) = floor((n+2)/3)^((n mod 3)+1). - Luce ETIENNE, Mar 01 2018
MATHEMATICA
Table[{n^2, n^3, n}, {n, 20}]//Flatten (* or *) LinearRecurrence[{0, 0, 4, 0, 0, -6, 0, 0, 4, 0, 0, -1}, {1, 1, 1, 4, 8, 2, 9, 27, 3, 16, 64, 4}, 60] (* Harvey P. Dale, May 26 2018 *)
CROSSREFS
Cf. A000463.
Cf. A010872.
Sequence in context: A011516 A088609 A163813 * A372297 A339571 A110653
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Aug 30 2005
STATUS
approved