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A227772
Sequence based on factorial representation converging to 1 in 2-adic numbers, and 0 in p-adic numbers for any other p.
1
0, 1, 3, 9, 105, 225, 945, 36225, 76545, 2253825, 9511425, 89345025, 1526349825, 26434433025, 287969306625, 12057038618625, 179439357722625, 5870438207258625, 37882306735898625, 1984203913277210625, 11715811945983770625, 982443713208463130625, 15594453174317362970625
OFFSET
1,3
COMMENTS
This is an example to show how a sequence can be constructed to converge to an arbitrary p-adic number chosen independently for each p.
LINKS
FORMULA
Solve for a(n) == 1 (mod A060818(n)) and a(n) == 0 (mod A049606), taking the least nonnegative residue.
EXAMPLE
5! = 2^3 * 3 * 5. Solving for m == 1 (mod 2^3), 0 (mod 3) and 0 (mod 5), we get m == 105 (mod 120), so we take a(5) = 105.
The factorial base representation is ...114111.
PROG
(PARI) a(n)=lift(chinese(Mod(1, denominator(polcoeff(pollegendre(n), n))), Mod(0, denominator(2^n/n!)))) /* Ralf Stephan, Aug 01 2013 */
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Ralf Stephan, Aug 01 2013
More terms from Jinyuan Wang, Jan 16 2021
STATUS
approved