A174944 Greatest number k such that sum of the n-th powers of the digits of k is greater than k.

99, 1999, 19999, 199999, 2999999, 29999999, 299999999, 2999999999, 29999999999, 299999999999, 2999999999999, 29999999999999

Offset

2,1

References

J.M. De Koninck, Ces nombres qui nous fascinent. Entry 19999 p.212. Ellipses, 2008.

Links

Table of n, a(n) for n=2..13.

Example

a(4) = 19999 is in the sequence because, if k > 19999, sum of 4th powers of digits < k.

Maple

with(numtheory):for k from 1 to 10 do:maxi:=0:for n from 1 to 2000000 do:l:=length(n):n0:=n:s:=0:for  m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :s:=s+u^k:od: if s>n  and s>maxi then maxi:=s:n1:=n:else fi:od:print(n1):od:

Crossrefs

Sequence in context: A196808 A305721 A197372 * A221330 A246247 A157370

Adjacent sequences: A174941 A174942 A174943 * A174945 A174946 A174947

Keyword

nonn,base

Author

Michel Lagneau, Dec 02 2010

Status

approved