OFFSET
1,3
COMMENTS
The largest prime power factor of a number n is given by A034699(n).
EXAMPLE
The first terms, alongside A000961(n) and the set of numbers k such that A034699(k) = A000961(n), are:
n a(n) A000961(n) S(n)
-- ---- ---------- ----
1 1 1 { 1 }
2 1 2 { 2 }
3 2 3 { 3, 6 }
4 2 4 { 4, 12 }
5 6 5 { 5, 10, 15, 20, 30, 60 }
6 12 7 { 7, 14, 21, 28, 35, 42, 70, 84, 105, 140, 210, 420 }
7 8 8 { 8, 24, 40, 56, 120, 168, 280, 840 }
PROG
(PARI) my(l=1); for (k=1, 103, if (omega(k) <= 1, l = lcm(l, k); print1 (numdiv(l/k) ", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
Rémy Sigrist, May 27 2018
STATUS
approved