OFFSET
1,2
COMMENTS
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..10001
PROG
(PARI) isA327165(n) = { fordiv(n, d, if(n==d*sigma(d), return(1))); (0); };
(PARI) A327165list(up_to) = { my(res = List()); for(i = 1, sqrtint(up_to), c = i*sigma(i); if(c <= up_to, listput(res, c))); listsort(res, 1); Vec(res); }; \\ From David A. Corneth, Sep 18 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 18 2019
STATUS
approved