A115306 a(n) = if n<6 then n else 6*a(floor(n/6)) + 5 - n mod 6.

1, 2, 3, 4, 5, 11, 10, 9, 8, 7, 6, 17, 16, 15, 14, 13, 12, 23, 22, 21, 20, 19, 18, 29, 28, 27, 26, 25, 24, 35, 34, 33, 32, 31, 30, 71, 70, 69, 68, 67, 66, 65, 64, 63, 62, 61, 60, 59, 58, 57, 56, 55, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 107

Offset

1,2

Comments

Self-inverse permutation of the natural numbers;

if n is written in base 6 representation, then a(n) is the value after replacing all digits d (but not the leading one) by 5-d.

Links

Table of n, a(n) for n=1..72.

Index entries for sequences that are permutations of the natural numbers

Formula

a(n) = A115310(n+4, 5).

Mathematica

a[n_]:=If[n<6, n, 6*a[Floor[n/6]]+5-Mod[n, 6]]; Table[a[n], {n, 72}] (* James C. McMahon, Aug 11 2024 *)

Crossrefs

Cf. A054429, A115303, A115304, A115305, A115307, A115308, A115309, A106649.

Sequence in context: A345320 A160000 A245448 * A171592 A265567 A265551

Adjacent sequences: A115303 A115304 A115305 * A115307 A115308 A115309

Keyword

nonn,base,easy

Author

Reinhard Zumkeller, Jan 20 2006

Status

approved