OFFSET
1,1
COMMENTS
If k is a term, then 2*k + 2 is a term of A125246. - Jinyuan Wang, Apr 08 2020
PROG
(PARI) isok(k) = sigma(2*k+2) == 4*k; \\ Michel Marcus, Apr 06 2020
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Benoit Cloitre, Feb 04 2002
EXTENSIONS
a(9) from Benoit Cloitre and Neven Juric (neven.juric(AT)apis-it.hr), May 21 2004
a(10)-a(15) from Donovan Johnson, Jan 31 2009
a(16)-a(18) from Jinyuan Wang, Apr 06 2020
STATUS
approved