0,2

Number of m >= 1 with m = sum of digits of m^n.

T. D. Noe, Table of n, a(n) for n=0..1000

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

a(n) = 1 + A046471(n). - T. D. Noe, Nov 26 2008

a(7)=9 because:

1^7=1

18^7= 612220032 and 6+1+2+2+2+3+2=18

27^7= 10460353203 and 1+4+6+3+5+3+2+3=27

31^7= 27512614111 and 2+7+5+1+2+6+1+4+1+1+1=31

34^7= 52523350144 and 5+2+5+2+3+3+5+1+4+4=34

43^7= 271818611107 and 2+7+1+8+1+8+6+1+1+1+7=43

53^7= 1174711139837 and 1+1+7+4+7+1+1+1+3+9+8+3+7=53

58^7= 2207984167552 and 2+2+7+9+8+4+1+6+7+5+5+2=58

68^7= 6722988818432 and 6+7+2+2+9+8+8+8+1+8+4+3+2=68

a(9)=4 because:

1^9=1

54^9=3904305912313344 and 3+9+4+3+5+9+1+2+3+1+3+3+4+4=54

71^9=45848500718449031 and 4+5+8+4+8+5+7+1+8+4+4+9+3+1=71

81^9=150094635296999121 and 1+5+9+4+6+3+5+2+9+6+9+9+9+1+2+1=81

Cf. A124359.

Cf. A152147 (table of m such that the sum of digits of m^n equals m)

Sequence in context: A160262 A107821 A154162 this_sequence A021523 A011436 A019877

Adjacent sequences: A046016 A046017 A046018 this_sequence A046020 A046021 A046022

nonn,base

David W. Wilson (davidwwilson(AT)comcast.net)

Examples provided by Paolo P. Lava (ppl(AT)spl.at), Oct 30 2006

Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion of Andrew Plewe, May 27 2007