A178204 Smith numbers of order 6; composite numbers n such that sum of digits^6 equal sum of digits^6 of its prime factors without the numbers in A176670 that have the same digits as its prime factors (without the zero digits).

40844882, 113986781, 130852098, 141176320, 168137185, 170774472, 178180163, 181681157, 181693781, 183161897, 187117638, 215149451, 261666000, 284804842, 294557945, 307711074, 335524949, 337194240, 344552927, 347391040, 355318188, 358831104, 368657536

Offset

1,1

Links

Donovan Johnson, Table of n, a(n) for n = 1..1000

Eric W. Weisstein, Smith Number

Example

a(4) = 141176320 = 2^9*5*55147;
3*1^6+2^6+3^6+4^6+6^6+7^6 = 1^6+9*2^6+4^6+3*5^6+7^6 = 169197

Mathematica

fQ[n_] := Block[{id = Sort@ IntegerDigits@ n, fid = Sort@ Flatten[ IntegerDigits@ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger@ n]}, While[ id[[1]] == 0, id = Drop[id, 1]]; While[ fid[[1]] == 0, fid = Drop[fid, 1]]; id != fid && Plus @@ (id^6) == Plus @@ (fid^6)]; k = 2; lst = {}; While[k < 50000001, If[fQ@ k, AppendTo[ lst, k]; Print@ k]; k++]; lst

Crossrefs

Cf. A006753 (Smith numbers), A176670, A174460, A178213, A178193, A178203.

Sequence in context: A017481 A017613 A015409 * A334583 A130681 A261658

Adjacent sequences: A178201 A178202 A178203 * A178205 A178206 A178207

Keyword

nonn,base

Author

Paul Weisenhorn, Dec 19 2010

Extensions

Example corrected by Donovan Johnson, Jan 02 2013

Status

approved