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A056524
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Palindromes with even number of digits.
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6
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0, 11, 22, 33, 44, 55, 66, 77, 88, 99, 1001, 1111, 1221, 1331, 1441, 1551, 1661, 1771, 1881, 1991, 2002, 2112, 2222, 2332, 2442, 2552, 2662, 2772, 2882, 2992, 3003, 3113, 3223, 3333, 3443, 3553, 3663, 3773, 3883, 3993, 4004, 4114, 4224, 4334, 4444, 4554
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Concatenation of n with reverse of n (keeping leading zeros in the reverse)
A178788(a(n)) = 0 for n > 1. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 30 2010]
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
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FORMULA
| a(n) = n*10^A055642(n)+A004086(n)
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PROG
| (Haskell)
a056524 n = a056524_list !! (n-1)
a056524_list = [read (ns ++ reverse ns) :: Integer |
n <- [0..], let ns = show n]
-- Reinhard Zumkeller, Dec 28 2011
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CROSSREFS
| Cf. A002113, A004086, A056525, A066492.
Sequence in context: A068900 A083852 * A110745 A020338 A052191 A110732
Adjacent sequences: A056521 A056522 A056523 * A056525 A056526 A056527
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KEYWORD
| base,easy,nonn
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AUTHOR
| Henry Bottomley (se16(AT)btinternet.com), Jun 16 2000
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