A073220 Terms of A072390 (sums of two powers of 13) divided by 2.

1, 7, 13, 85, 91, 169, 1099, 1105, 1183, 2197, 14281, 14287, 14365, 15379, 28561, 185647, 185653, 185731, 186745, 199927, 371293, 2413405, 2413411, 2413489, 2414503, 2427685, 2599051, 4826809, 31374259, 31374265, 31374343, 31375357

Offset: 1

Author

Jeremy Gardiner, Jul 21 2002

Keywords

• easy
• nonn

Examples

			a(4) = 85 = (11^2+11^0) / 2
		

Crossrefs

Cf. A072390.

Programs

Mathematica

Union[Total/@Tuples[13^Range[0,9],2]]/2 (* Harvey P. Dale, Sep 15 2011 *)

Formula

(13^n + 13^m) / 2, n = 0, 1, 2, 3 ..., m = 0, 1, 2, 3, ... n.