A073220 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..32.

FORMULA

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

EXAMPLE

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

MATHEMATICA

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

CROSSREFS