|
Search: id:A125832
|
|
|
| A125832 |
|
Numbers n which have exactly 14 representations as a product of two palindromes. |
|
+0
3
|
|
| 5426124, 8139186, 20017998, 21999978, 26690664, 26888862, 29333304, 49821684
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
EXAMPLE
|
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.
|
|
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}]
|
|
CROSSREFS
|
Cf. A116993, A125833, A125834.
Sequence in context: A022258 A092020 A029822 this_sequence A092019 A061164 A069316
Adjacent sequences: A125829 A125830 A125831 this_sequence A125833 A125834 A125835
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
Farideh Firoozbakht (mymontain(AT)yahoo.com), Dec 10 2006
|
|
|
Search completed in 0.002 seconds
|
