OFFSET
1,1
COMMENTS
The sequence is finite because the restricted sum of divisors of n, for n composite, is at least sqrt(n), while the sum of the fifth powers of the digits of n is at most 9^5*log_10(n+1). Last term is a(404) = 23184988999. - Giovanni Resta, Oct 05 2018
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..404 (full sequence)
EXAMPLE
k=118678 is in the sequence because 1^5 + 1^5 + 8^5 + 6^5 + 7^5 + 8^5 = 90121, and the sum of the divisors 1 < d < k = sigma(k) - k - 1 = 90121.
MATHEMATICA
Q[n_]:=Module[{a=Total[Rest[Most[Divisors[n]]]]}, a == Total[IntegerDigits[n]^5]]; Select[Range[2, 10^7], Q]
CROSSREFS
KEYWORD
nonn,base,fini,full
AUTHOR
Michel Lagneau, Dec 15 2011
EXTENSIONS
a(11)-a(25) and keywords fini and full added by Giovanni Resta, Oct 05 2018
STATUS
approved