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A017224
a(n) = (9*n + 5)^4.
3
625, 38416, 279841, 1048576, 2825761, 6250000, 12117361, 21381376, 35153041, 54700816, 81450625, 116985856, 163047361, 221533456, 294499921, 384160000, 492884401, 623201296, 777796321, 959512576
OFFSET
0,1
FORMULA
a(n) = A000583(A017221(n)).
From Harvey P. Dale, Apr 27 2016: (Start)
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5).
G.f.: (625 + 35291*x + 94011*x^2 + 27281*x^3 + 256*x^4)/(1-x)^5. (End)
E.g.f.: (625 + 37791*x + 101817*x^2 + 53946*x^3 + 6561*x^4)*exp(x). - G. C. Greubel, Jan 06 2023
MATHEMATICA
(9*Range[0, 20]+5)^4 (* Harvey P. Dale, Apr 27 2016 *)
PROG
(Magma) [(9*n+5)^4: n in [0..35]] ; // Vincenzo Librandi, Jul 24 2011
(SageMath) [(9*n+5)^4 for n in range(41)] # G. C. Greubel, Jan 06 2023
CROSSREFS
Sequences of the form (9*n+5)^k: A017221 (k=1), A017222 (k=2), A017223 (k=3), this sequence (k=4), A017225 (k=5), A017226 (k=6), A017227 (k=7), A017228 (k=8), A017229 (k=9), A017230 (k=10), A017231 (k=11).
Cf. A000583 (n^4).
Sequence in context: A080175 A017128 A180259 * A106321 A017332 A167039
KEYWORD
nonn,easy
STATUS
approved