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A226970
Fixed points for the operation of repeatedly replacing a number with the sum of the ninth powers of its digits.
7
0, 1, 146511208, 472335975, 534494836, 912985153
OFFSET
1,3
COMMENTS
The only six integers equal to the sum of the ninth powers of their digits.
This is row n=9 of A252648. For a d-digit number n >= 10^(d-1), the sum of 9th powers of its digits is <= 9^9*d, therefore n <= 4112105981. - M. F. Hasler, Apr 12 2015
EXAMPLE
a(3) = A003321(9);
a(4) = 472335975 = 4^9 + 7^9 + 2^9 + 3^9 + 3^9 + 5^9 + 9^9 + 7^9 + 5^9.
PROG
(PARI) is_A226970(n)=n==sum(i=1, #n=digits(n), n[i]^9)
for(n=0, 4112105981, is_A226970(n)&&print1(n", ")) \\ M. F. Hasler, Apr 12 2015
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
Michel Lagneau, Jun 24 2013
STATUS
approved