A226831 Numbers of the form 7^j + 9^k, for j and k >= 0.

2, 8, 10, 16, 50, 58, 82, 88, 130, 344, 352, 424, 730, 736, 778, 1072, 2402, 2410, 2482, 3130, 6562, 6568, 6610, 6904, 8962, 16808, 16816, 16888, 17536, 23368, 59050, 59056, 59098, 59392, 61450, 75856, 117650, 117658, 117730, 118378, 124210, 176698, 531442

Offset

1,1

Links

T. D. Noe, Table of n, a(n) for n = 1..10000

Mathematica

a = 7; b = 9; mx = 600000; Union[Flatten[Table[a^n + b^m, {m, 0, Log[b, mx]}, {n, 0, Log[a, mx - b^m]}]]]

Prog

(PARI) list(lim)=my(v=List(), J, K); for(j=0, logint((lim\=1)-1, 7), J=7^j; K=1; while(J+K<=lim, listput(v, J+K); K*=9)); Set(v) \\ Charles R Greathouse IV, Feb 18 2021

Crossrefs

Cf. A004050 (2^j + 3^k), A226806-A226832 (cases to 8^j + 9^k).

Cf. A226795 ((7^j + 9^k)/2).

Sequence in context: A126002 A110913 A038638 * A197115 A288824 A190042

Adjacent sequences: A226828 A226829 A226830 * A226832 A226833 A226834

Keyword

nonn,easy

Author

T. D. Noe, Jun 19 2013

Status

approved