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A017030
a(n) = (7*n + 4)^2.
2
16, 121, 324, 625, 1024, 1521, 2116, 2809, 3600, 4489, 5476, 6561, 7744, 9025, 10404, 11881, 13456, 15129, 16900, 18769, 20736, 22801, 24964, 27225, 29584, 32041, 34596, 37249, 40000, 42849, 45796
OFFSET
0,1
FORMULA
a(n) = A017029(n)^2. - Michel Marcus, Nov 11 2013
Sum{n>=0} 1/a(n) = psi'(4/7)/49 = 0.080438723... - R. J. Mathar, May 07 2024
MAPLE
A017030:=n->(7*n+4)^2; seq(A017030(n), n=0..100); # Wesley Ivan Hurt, Nov 11 2013
MATHEMATICA
Table[(7n+4)^2, {n, 0, 100}] (* Wesley Ivan Hurt, Nov 11 2013 *)
LinearRecurrence[{3, -3, 1}, {16, 121, 324}, 40] (* Harvey P. Dale, May 25 2019 *)
PROG
(Magma) [(7*n+4)^2: n in [0..40] ]; // Vincenzo Librandi, Jul 16 2011
(PARI) a(n)=(7*n+4)^2 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
Sequence in context: A135794 A161851 A171584 * A082921 A191902 A294140
KEYWORD
nonn,easy
STATUS
approved