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
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
KEYWORD
nonn,base,easy
AUTHOR
Reinhard Zumkeller, Jan 20 2006
STATUS
approved