A069554 Smallest k > 0 with gcd(k, rev(k)) = n, where rev(k) is digit reversal of k, or 0 if no such k exists.

1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 11, 48, 1495, 2072, 510, 2192, 1156, 234, 2489, 0, 168, 22, 3358, 840, 5200, 2678, 2889, 4256, 5017, 0, 1178, 21920, 33, 20774, 5075, 216, 1009009009009, 2318, 1677, 0, 1066, 2436, 15523, 44, 540, 20516, 30644, 8400, 18718, 0, 1479, 21788

Offset: 1

Author

Amarnath Murthy, Mar 22 2002

Keywords

• nonn
• base

Examples

			a(12) = 48 as gcd(48,84) = 12.
		

Programs

PARI

a(n) = {if (n % 10 == 0, return (0)); k = 1; while (gcd(k, subst(Polrev(digits(k)), x, 10)) != n, k++); k;} \\ Michel Marcus, Sep 14 2013

Extensions

Edited by David W. Wilson and Don Reble, Jun 04 2002