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A095412
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Exponents k such that the sum of decimal digits of 2^k is also a power of 2.
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6
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0, 1, 2, 3, 9, 36, 85, 176, 194, 200, 375, 1517, 1523, 3042, 5953, 6043, 6109, 12068, 12104, 96251, 193734, 386797, 387589, 1545477, 3092224, 3098800, 6188717, 6191693, 6199469, 24753865, 99084345
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OFFSET
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1,3
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LINKS
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EXAMPLE
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2^9 = 512 with digit sum = 8;
2^36 = 68719476736 with digit sum = 64;
2^85 = 38685626227668133590597632 with digit sum = 128;
2^96251 has a decimal digit sum of 131072.
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MATHEMATICA
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Do[If[IntegerQ[Log[2, Plus@@IntegerDigits[2^n]]], Print[n] ], {n, 0, 10^6}];
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PROG
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(PARI) isp(n) = (n==1) || (n==2) || (ispower(n, , &k) && (k==2));
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CROSSREFS
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Cf. A001370 (sum of digits of 2^n).
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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