|
| |
|
|
A144766
|
|
Members of A144719 that are themselves decimal palindromes.
|
|
0
| |
|
|
121, 10001, 10201, 36763, 1226221, 7673767, 12467976421, 1030507050301, 1120237320211, 1225559555221, 1234469644321, 1334459544331, 100330272033001, 100827848728001, 101222252222101, 103023070320301, 121363494363121, 134312696213431
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Presumed infinite, but it is difficult to find more terms.
The earlier claim that this sequence is a subsequence of A046450 was incorrect, as the counter-example of 7673767 =97*79111 shows. The reason is that A046450 checks only concatenations in the natural order of the prime factors, but this sequence here allows for both orders, 97//79111 as well as 79111//97, to be palindromic. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 22 2009]
3*10^14 < a(19) <= 10022212521222001. - Donovan Johnson
|
|
|
FORMULA
| Subsequence of (A144719 INTERSECT A046328). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 22 2009]
|
|
|
EXAMPLE
| 10001 = 73 * 137; 73137 is a palindrome.
|
|
|
CROSSREFS
| Cf. A002113, A046450, A144719
Sequence in context: A069600 A018849 A011814 * A176923 A058412 A006102
Adjacent sequences: A144763 A144764 A144765 * A144767 A144768 A144769
|
|
|
KEYWORD
| base,hard,more,nonn
|
|
|
AUTHOR
| Reikku Kulon (reikku(AT)gmail.com), Sep 20 2008
|
|
|
EXTENSIONS
| a(7)-a(18) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 08 2010
|
| |
|
|
