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A255873
The first nonzero digit of n/7.
1
1, 2, 4, 5, 7, 8, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
1,2
LINKS
EXAMPLE
The leading (most significant) digit of 22/7 in A068028 is 3, so a(22)=3.
MAPLE
A255873 := proc(n)
local nshf ;
nshf := n/7 ;
while nshf < 1 do
nshf := 10*nshf;
end do;
while nshf >= 10 do
nshf := nshf/10;
end do;
floor(nshf) ;
end proc: # R. J. Mathar, May 28 2016
MATHEMATICA
f[n_] := RealDigits[n/7, 10, 9][[1, 1]]; Array[f, 105] (* Robert G. Wilson v, Mar 08 2015 *)
PROG
(PARI) a(n) = {my(x = n/7.0); if (x < 1, x *= 10); while (x >= 10, x /= 10); floor(x); } \\ Michel Marcus, Mar 12 2015
CROSSREFS
Cf. A020806 (1/7), A068028 (22/7), A216606 (360/7).
Sequence in context: A112233 A062249 A081404 * A141425 A081516 A023962
KEYWORD
nonn,base
AUTHOR
Kit Scriven, Mar 08 2015
STATUS
approved