login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A069805
Smallest k>n such that tau(n) divides tau(k)=A000005(k).
3
2, 3, 5, 9, 6, 8, 8, 10, 12, 14, 12, 18, 14, 15, 21, 48, 18, 20, 20, 28, 22, 24, 24, 30, 28, 27, 30, 32, 30, 40, 32, 44, 34, 35, 38, 100, 38, 39, 40, 42, 42, 54, 44, 45, 50, 51, 48, 80, 50, 52, 54, 60, 54, 56, 56, 66, 58, 60, 60, 72, 62, 65, 68, 192, 66, 70, 68, 72, 70, 78, 72
OFFSET
1,1
LINKS
PROG
(PARI) for(s=1, 100, n=s+1; while(frac(numdiv(n)/numdiv(s))>0, n++); print1(n, ", "); )
(PARI) a(n) = my(k=n+1); while(numdiv(k)%numdiv(n), k++); k; \\ Michel Marcus, Sep 15 2018
CROSSREFS
Cf. A000005.
Cf. A140635 (without k>n constraint).
Sequence in context: A342444 A011026 A374531 * A123923 A045965 A323390
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, May 01 2002
STATUS
approved