This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A227772 #18 Jan 17 2021 11:46:28 %S A227772 0,1,3,9,105,225,945,36225,76545,2253825,9511425,89345025,1526349825, %T A227772 26434433025,287969306625,12057038618625,179439357722625, %U A227772 5870438207258625,37882306735898625,1984203913277210625,11715811945983770625,982443713208463130625,15594453174317362970625 %N A227772 Sequence based on factorial representation converging to 1 in 2-adic numbers, and 0 in p-adic numbers for any other p. %C A227772 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. %H A227772 Jinyuan Wang, <a href="/A227772/b227772.txt">Table of n, a(n) for n = 1..450</a> %F A227772 Solve for a(n) == 1 (mod A060818(n)) and a(n) == 0 (mod A049606), taking the least nonnegative residue. %e A227772 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. %e A227772 The factorial base representation is ...114111. %o A227772 (PARI) a(n)=lift(chinese(Mod(1,denominator(polcoeff(pollegendre(n), n))),Mod(0,denominator(2^n/n!)))) /* _Ralf Stephan_, Aug 01 2013 */ %Y A227772 Cf. A000142, A049606, A060818, A007623. %K A227772 nonn %O A227772 1,3 %A A227772 _Franklin T. Adams-Watters_, Jul 30 2013 %E A227772 More terms from _Ralf Stephan_, Aug 01 2013 %E A227772 More terms from _Jinyuan Wang_, Jan 16 2021