A007943 Concatenation of sequence (1,3,..,2n-1,2n,2n-2,..,2).

12, 1342, 135642, 13578642, 13579108642, 135791112108642, 1357911131412108642, 13579111315161412108642, 135791113151718161412108642, 1357911131517192018161412108642

Offset

1,1

References

M. Le, Perfect Powers in the Smarandache Permutation Sequence, Smarandache Notions Journal, Vol. 10, No. 1-2-3, 1999, 148-149.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..184

F. Smarandache, Only Problems, Not Solutions!

Mathematica

Table[FromDigits[Join[Flatten[IntegerDigits/@Range[1, 2n+1, 2]], Flatten[ IntegerDigits/@ Range[2n+2, 2, -2]]]], {n, 0, 10}] (* Harvey P. Dale, Jul 30 2021 *)

Crossrefs

Cf. A007942.

Sequence in context: A071309 A067108 A240627 * A015512 A004145 A296609

Adjacent sequences: A007940 A007941 A007942 * A007944 A007945 A007946

Keyword

nonn,base

Author

R. Muller

Status

approved