A334690 a(n) is the number of points in the interior of the n-th figure shown in A255011 (meaning the figure with 4n points on the perimeter).

1, 29, 245, 801, 2737, 4801, 12265, 19209, 33513, 49537, 87641, 101933, 178413, 220057, 286297, 379033, 551601, 606169, 880217, 951365, 1208965, 1507433, 1947785, 2002573, 2624309, 3055989, 3550317, 3954937, 5068921, 5062033, 6669541, 7081841, 8143061, 9364953, 10296329, 10918073, 13772225, 14842297, 16312317

Offset: 1

Author

Scott R. Shannon and N. J. A. Sloane, May 17 2020

Keywords

• nonn

Comments

a(n) = A331449(n) - 4*n. Computed from Lars Blomberg's b-file for A331449.

Links

• N. J. A. Sloane, Table of n, a(n) for n = 1..52

Crossrefs

Cf. A255011, A331448, A331449.

These are the sums of the rows in A334691.