A125832 Numbers k which have exactly 14 representations as a product of two palindromes.

5426124, 8139186, 20017998, 21999978, 26690664, 26888862, 29333304, 49821684, 73267326, 97689768, 98666568, 146534652, 147999852, 220197978, 271333062, 274019262, 320221902, 403696293, 471535064, 489372884, 516019504, 518221704

Offset: 1

Author

Farideh Firoozbakht, Dec 10 2006

Keywords

• base
• nonn

Examples

			26888862 is in the sequence since 26888862 =
 1*26888862 = 2*13444431 = 11*2444442 = 22*1222221 = 111*242242 = 121*222222 = 222*121121 =
 242*111111 = 1001*26862 = 1221*22022 = 1331*20202 = 2002*13431 = 2442*11011 = 2662*10101.
		

Crossrefs

Cf. A116993, A125833, A125834.

Programs

Mathematica

f[n_]:=f[n]=Length[Select[Divisors[n],#<=n^(1/2)&&FromDigits[ Reverse[IntegerDigits[ # ]]]==#&&FromDigits[Reverse[IntegerDigits [n/# ]]]==n/#&]];Do[If[f[n]==14,Print[n]],{n,50000000}]

Extensions

a(9)-a(22) from Donovan Johnson, Aug 05 2009