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A069881
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Numbers n such that n and 2n+1 are both palindromes.
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0
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1, 2, 3, 4, 5, 55, 151, 161, 171, 181, 191, 252, 262, 272, 282, 292, 353, 363, 373, 383, 393, 454, 464, 474, 484, 494, 555, 5555, 15051, 15151, 15251, 15351, 15451, 16061, 16161, 16261, 16361, 16461, 17071, 17171, 17271, 17371, 17471, 18081, 18181
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Note that any number with all digits = 5 (A002279) is part of this sequence. - Jim McCann (jmccann(AT)umich.edu), Jul 16 2002
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EXAMPLE
| 151 is a member as 2*151 + 1 = 303 is also a palindrome.
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PROG
| (Perl) $a = 1; while((@b = split("|", $a) and @c = split("|", 2*$a+1) and (join("", reverse(@b)) eq join("", @b) and join("", reverse(@c)) eq join("", @c) and eval("print \"\$a \"; return 0; "))) or ++$a) { }
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CROSSREFS
| Sequence in context: A024638 A037330 A062939 * A004856 A037327 A075832
Adjacent sequences: A069878 A069879 A069880 * A069882 A069883 A069884
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KEYWORD
| nonn,base
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AUTHOR
| Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 30 2002
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EXTENSIONS
| More terms from Jim McCann (jmccann(AT)umich.edu), Jul 16 2002
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