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A226816
Numbers of the form 3^j + 7^k, for j and k >= 0.
3
2, 4, 8, 10, 16, 28, 34, 50, 52, 58, 76, 82, 88, 130, 244, 250, 292, 344, 346, 352, 370, 424, 586, 730, 736, 778, 1072, 2188, 2194, 2236, 2402, 2404, 2410, 2428, 2482, 2530, 2644, 3130, 4588, 6562, 6568, 6610, 6904, 8962, 16808, 16810, 16816, 16834, 16888
OFFSET
1,1
MATHEMATICA
a = 3; b = 7; mx = 20000; Union[Flatten[Table[a^n + b^m, {m, 0, Log[b, mx]}, {n, 0, Log[a, mx - b^m]}]]]
CROSSREFS
Cf. A004050 (2^j + 3^k), A226806-A226832 (cases to 8^j + 9^k).
Cf. A226791 ((3^j + 7^k)/2).
Sequence in context: A161374 A272062 A045795 * A371291 A335238 A337666
KEYWORD
nonn
AUTHOR
T. D. Noe, Jun 19 2013
STATUS
approved