A068636 a(n) = Min(n, R(n)), where R(n) (A004086) = digit reversal of n.

1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 11, 12, 13, 14, 15, 16, 17, 18, 19, 2, 12, 22, 23, 24, 25, 26, 27, 28, 29, 3, 13, 23, 33, 34, 35, 36, 37, 38, 39, 4, 14, 24, 34, 44, 45, 46, 47, 48, 49, 5, 15, 25, 35, 45, 55, 56, 57, 58, 59, 6, 16, 26, 36, 46, 56, 66, 67, 68, 69, 7, 17, 27, 37, 47, 57

Offset: 1

Author

Amarnath Murthy, Feb 27 2002

Keywords

• base
• easy
• nonn
• look
• hear

Comments

a(n) = A004185(n) for n <= 100. - Reinhard Zumkeller, Apr 03 2015

Examples

			a(12) = min(12,21) = 12. a(34632) = min(34632,23643) = 23643.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A068637, A004086, A004185.

Programs

Haskell

a068636 n = min n $ a004086 n  -- Reinhard Zumkeller, Apr 03 2015

Maple

a:= n-> min(n,(s-> parse(cat(seq(s[-i], i=1..length(s)))))(""||n)):
seq(a(n), n=1..100);  # Alois P. Heinz, Aug 22 2015

Mathematica

Table[Min[n,IntegerReverse[n]],{n,80}] (* The program uses the IntegerReverse function from Mathematica version 10 *) (* Harvey P. Dale, Nov 27 2015 *)

Python

def A068636(n): return min(n,int(str(n)[::-1])) # Chai Wah Wu, Jun 26 2025