A071249 Numbers k such that gcd(k, R(k)) > 1, where R(k) (A004086) is the digit reversal of k.

2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 18, 20, 21, 22, 24, 26, 27, 28, 30, 33, 36, 39, 40, 42, 44, 45, 46, 48, 50, 51, 54, 55, 57, 60, 62, 63, 64, 66, 68, 69, 70, 72, 75, 77, 78, 80, 81, 82, 84, 86, 87, 88, 90, 93, 96, 99, 101, 102, 105, 108, 110, 111, 114, 117, 120, 121

Offset: 1

Author

Amarnath Murthy, May 21 2002

Keywords

• base
• nonn

Comments

Numbers k such that A055483(k) > 1. - Reinhard Zumkeller, Jun 18 2013

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A004086, A055483, A226778 (complement).

Programs

Haskell

a071249 n = a071249_list !! (n-1)
a071249_list = filter ((> 1) . a055483) [1..]
-- Reinhard Zumkeller, Jun 18 2013

Mathematica

Select[ Range[125], GCD[ #, FromDigits[ Reverse[ IntegerDigits[ # ]]]] > 1 & ]

Extensions

Edited by Robert G. Wilson v, Jun 07 2002

Definition corrected by N. J. A. Sloane, Aug 27 2020 following a suggestion from José Hernández Santiago