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A073045 Nonprime solutions to sopfr(n) = S(n), where sopfr(n) = A001414 and S(n) = A002034. 1
4, 9, 25, 27, 49, 121, 125, 169, 289, 343, 361, 529, 625, 841, 961, 1331, 1369, 1681, 1849, 2197, 2209, 2401, 2809, 3125, 3481, 3721, 4489, 4913, 5041, 5329, 6241, 6859, 6889, 7921, 9409, 10201, 10609, 11449, 11881, 12167, 12769, 14641, 16129, 16807 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
sopfr(9) = S(9) = 6 and 6 is composite, so 9 is a term.
PROG
(PARI) {for(n=1, 17000, if(!isprime(n), s=0; fac=factor(n); for(i=1, matsize(fac)[1], s=s+fac[i, 1]*fac[i, 2]); m=1; p=1; while(p%n>0, m++; p=p*m); if(s==m, print1(n, ", "))))}
CROSSREFS
Sequence in context: A093867 A126638 A340640 * A045967 A336445 A232241
KEYWORD
nonn
AUTHOR
Jason Earls, Aug 24 2002
EXTENSIONS
Edited and extended by Klaus Brockhaus, Aug 26 2002
STATUS
approved

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Last modified May 27 16:04 EDT 2024. Contains 372880 sequences. (Running on oeis4.)