A173536 A173039(n) + A173259(n).

1, 0, 1, 9, 4, 25, 49, 16, 81, 121, 36, 169, 225, 64, 289, 361, 100, 441, 529, 144, 625, 729, 196, 841, 961, 256, 1089, 1225, 324, 1369, 1521, 400, 1681, 1849, 484, 2025, 2209, 576, 2401, 2601, 676, 2809, 3025, 784, 3249, 3481, 900, 3721, 3969, 1024, 4225, 4489, 1156, 4761, 5041, 1296, 5329

Offset

1,4

Comments

A permutation of the squared A023443, or -- if a(1) is discarded to avoid duplication -- of A000290.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (0,0,3,0,0,-3,0,0,1).

Formula

a(n)= +3*a(n-3) -3*a(n-6) +a(n-9).

G.f.: -x*(1+x^2+6*x^3+4*x^4+22*x^5+25*x^6+4*x^7+9*x^8) / ( (x-1)^3*(1+x+x^2)^3 ).

a(3n+2) = A016742(n). a(3n) = A016754(2n). a(3n+1) = A016754(2n-1).

Mathematica

LinearRecurrence[{0, 0, 3, 0, 0, -3, 0, 0, 1}, {1, 0, 1, 9, 4, 25, 49, 16, 81}, 60] (* Harvey P. Dale, May 24 2026 *)

Crossrefs

Sequence in context: A317739 A174679 A168077 * A014717 A104728 A058093

Adjacent sequences: A173533 A173534 A173535 * A173537 A173538 A173539

Keyword

nonn,easy

Author

Paul Curtz, Nov 23 2010

Status

approved