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%I #5 Aug 29 2016 11:59:43
%S 2,9,10,17,65,73,82,89,145,513,521,593,730,737,793,1241,4097,4105,
%T 4177,4825,6562,6569,6625,7073,10657,32769,32777,32849,33497,39329,
%U 59050,59057,59113,59561,63145,91817,262145,262153,262225,262873,268705,321193,531442
%N Numbers of the form 8^j + 9^k, for j and k >= 0.
%H T. D. Noe, <a href="/A226832/b226832.txt">Table of n, a(n) for n = 1..10000</a>
%t a = 8; b = 9; mx = 600000; Union[Flatten[Table[a^n + b^m, {m, 0, Log[b, mx]}, {n, 0, Log[a, mx - b^m]}]]]
%o (PARI) ispowof(n,k)=k^valuation(n,k)==n
%o is(n)=if(n%8 != 1, return(ispowof(n-1,9))); for(k=0,logint(n-1,9), if(ispowof(n-9^k,8), return(1))); 0 \\ _Charles R Greathouse IV_, Aug 29 2016
%Y Cf. A004050 (2^j + 3^k), A226806-A226831 (cases to 7^j + 9^k).
%K nonn
%O 1,1
%A _T. D. Noe_, Jun 19 2013
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