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A214677
a(n) = n represented in bijective base-7 numeration.
3
1, 2, 3, 4, 5, 6, 7, 11, 12, 13, 14, 15, 16, 17, 21, 22, 23, 24, 25, 26, 27, 31, 32, 33, 34, 35, 36, 37, 41, 42, 43, 44, 45, 46, 47, 51, 52, 53, 54, 55, 56, 57, 61, 62, 63, 64, 65, 66, 67, 71, 72, 73, 74, 75, 76, 77, 111, 112, 113, 114, 115, 116, 117, 121, 122
OFFSET
1,2
LINKS
R. R. Forslund, A logical alternative to the existing positional number system, Southwest Journal of Pure and Applied Mathematics, Vol. 1, 1995, 27-29.
Eric Weisstein's World of Mathematics, Zerofree
MAPLE
a:= proc(n) local d, l, m; m:= n; l:= NULL;
while m>0 do d:= irem(m, 7, 'm');
if d=0 then d:=7; m:= m-1 fi;
l:= d, l
od; parse(cat(l))
end:
seq(a(n), n=1..100);
MATHEMATICA
With[{b = 7}, Flatten@ Table[FromDigits[PadLeft[IntegerDigits[k, b], n] /. k_ :> k + 1], {n, 3}, {k, 0, b^n - 1}] ] (* Michael De Vlieger, Sep 16 2023 *)
CROSSREFS
Column k=7 of A214676.
Sequence in context: A102453 A265571 A265555 * A275910 A032971 A099466
KEYWORD
nonn,base,easy
AUTHOR
Alois P. Heinz, Jul 25 2012
STATUS
approved