0,2

Table of n, a(n) for n=0..84.

a(n) = 6 for n >= 4.

(PARI) Vec((1 + x)*(1 + 2*x + 2*x^2 - 2*x^3) / (1 - x) + O(x^80)) \\ Colin Barker, Nov 21 2019

Row 3 of array in A329504.

Sequence in context: A114610 A200390 A137209 * A032566 A330555 A200357

Adjacent sequences: A329503 A329504 A329505 * A329507 A329508 A329509

nonn,easy

N. J. A. Sloane, Nov 20 2019

approved