This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A073045 Nonprime solutions to sopfr(n) = S(n), where sopfr(n) = A001414 and S(n) = A002034. 0
 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 Cf. A074583. Sequence in context: A175119 A093867 A126638 * A045967 A232241 A163836 Adjacent sequences:  A073042 A073043 A073044 * A073046 A073047 A073048 KEYWORD nonn AUTHOR Jason Earls, Aug 24 2002 EXTENSIONS Edited and extended by Klaus Brockhaus, Aug 26 2002 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 17 17:52 EST 2019. Contains 320222 sequences. (Running on oeis4.)