A209974 a(n) = A209973(n)/4.

0, 0, 3, 5, 9, 13, 19, 25, 33, 39, 51, 61, 69, 81, 99, 107, 123, 139, 157, 175, 191, 203, 233, 255, 271, 291, 327, 345, 369, 397, 421, 451, 483, 503, 551, 575, 599, 635, 689, 713, 745, 785, 821, 863, 903, 927, 993, 1039, 1071, 1113, 1173

Offset: 0

Author

Clark Kimberling, Mar 16 2012

Keywords

• nonn

Comments

For a guide to related sequences, see A210000.

Crossrefs

Cf. A210000.

Cf. A000010, A126246.

Programs

Mathematica

(See the Mathematica section at A210000.)

Formula

Apparently, a(n) = a(n-1) + 2*A126246(n) - A000010(n) for n >= 2. - Pontus von Brömssen, Jun 28 2021