A226971 Numbers k such that the sum of digits of k^7 is equal to k.

0, 1, 18, 27, 31, 34, 43, 53, 58, 68

Offset

1,3

Comments

Only the ten integers listed have this property.

Links

Table of n, a(n) for n=1..10.

Example

a(3) = 18 because 18^7 = 612220032 and 6+1+2+2+2+0+0+3+2 = 18.

Mathematica

Select[Range[0, 100], #==Total[IntegerDigits[#^7]]&]

Prog

(Magma) [n: n in [0..80] | &+Intseq(n^7) eq n]; // Vincenzo Librandi, Feb 23 2015
(Sage) [n for n in (0..70) if sum((n^7).digits()) == n] # Bruno Berselli, Feb 23 2015

Crossrefs

Cf. A046459, A055575, A055576, A055577.

Cf. A152147.

Sequence in context: A080910 A347826 A036763 * A281918 A186129 A284672

Adjacent sequences: A226968 A226969 A226970 * A226972 A226973 A226974

Keyword

nonn,base,fini,full

Author

Michel Lagneau, Jun 24 2013

Status

approved