A106323 Smaller of number pair whose squares are reversals of each other, with no leading zeros allowed.

12, 13, 33, 102, 103, 112, 113, 122, 1002, 1003, 1011, 1012, 1013, 1021, 1022, 1031, 1102, 1103, 1112, 1113, 1121, 1122, 1202, 1212, 2012, 2022, 3168, 10002, 10003, 10011, 10012, 10013, 10021, 10022, 10031, 10102, 10103, 10111, 10112, 10113

Offset: 1

Author

Lekraj Beedassy, Apr 29 2005

Keywords

• base
• nonn

Comments

For numbers whose squares are the reversal of a(n)^2, see A106324.

Examples

			33 is in the sequence because 33^2=1089 and we have 9801=99^2. Likewise,122^2=14884 and we have 48841=221^2.
		

Crossrefs

Cf. A035090; A035123.

Half of A035123.

Programs

PARI

isok(n) = {if (n % 10 == 0, return (0)); d = digits(n^2, 10); m = sum(k=0, #d-1, d[k+1]*10^(k)); if (! issquare(m), return (0)); return (n < sqrtint(m));} \\ Michel Marcus, Jul 28 2013

Extensions

Corrected and extended by Joshua Zucker, May 12 2006