OFFSET
0,5
COMMENTS
a(0) = 1 by convention.
LINKS
FORMULA
a(n) = 1 iff n belongs to A059590.
EXAMPLE
For n = 1000000:
- the factorial base expansion of 1000000 is "2, 6, 6, 2, 5, 1, 2, 2, 0",
- so a(1000000) = lcm(1, 2, 5, 6) = 30.
PROG
(PARI) a(n) = { my (v=1); for (r=2, oo, if (n==0, return (v), n%r, v=lcm(v, n%r)); n\=r) }
CROSSREFS
KEYWORD
AUTHOR
Rémy Sigrist, Apr 17 2021
STATUS
approved