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A030655
Pair up the numbers.
4
12, 34, 56, 78, 910, 1112, 1314, 1516, 1718, 1920, 2122, 2324, 2526, 2728, 2930, 3132, 3334, 3536, 3738, 3940, 4142, 4344, 4546, 4748, 4950, 5152, 5354, 5556, 5758, 5960, 6162, 6364, 6566, 6768, 6970, 7172, 7374, 7576, 7778, 7980, 8182, 8384, 8586
OFFSET
1,1
COMMENTS
That is, a(n) is the concatenation of 2n-1 and 2n. - Charles R Greathouse IV, Aug 07 2012
LINKS
MATHEMATICA
FromDigits[Flatten[IntegerDigits/@{#}]]&/@Partition[Range[90], 2] (* Harvey P. Dale, Sep 28 2011 *)
PROG
(Magma) [Seqint(Intseq(n+1) cat Intseq(n)): n in [1..86 by 2]]; // Bruno Berselli, Jun 18 2011
(PARI) a(n)=eval(concat(Str(2*n-1), 2*n)) \\ Charles R Greathouse IV, Jun 18, 2011
CROSSREFS
Cf. A030656.
Subsequence of A005843.
Sequence in context: A141694 A228595 A077295 * A098080 A068517 A113748
KEYWORD
base,nonn,easy
EXTENSIONS
More terms from Erich Friedman.
STATUS
approved