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

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

Offset: 1

Author

R. Muller

Keywords

• nonn
• base

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!

Crossrefs

Cf. A007942.

Programs

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 *)