OFFSET
1,2
COMMENTS
a(n) == 3 (mod 4) for n > 1, since A072347(2k) = A072347(floor(k/2)) and A072347(4k+1) = A072347(2k+1). - Robert Israel, May 04 2016
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..10000 (first 3341 terms from Robert Israel)
Rémy Sigrist, Colored logarithmic scatterplot of a(n) for n = 1..10000 (where the color is function of the Hamming weight of a(n))
MAPLE
# using procedure a from A072347
R[1]:= 0:
for n from 3 to 100000 by 4 do
v:= a(n);
if not assigned(R[v]) then R[v]:= n
fi
od:
for n from 1 while assigned(R[n]) do od:
seq(R[i], i=1..n-1); # Robert Israel, May 04 2016
MATHEMATICA
Block[{c, s}, c[w_] := With[{n = Length@ w}, Which[n == 0, 1, n == 1, First@ w, True, Last[w] c[Most@ w] + c[Most@ Most@ w]]]; s = {1}~Join~Array[c[IntegerDigits[#, 2]] &, 10^4]; TakeWhile[Array[-1 + FirstPosition[s, #][[1]] &, 50], IntegerQ]] (* Michael De Vlieger, Jan 20 2018, after Jean-François Alcover at A072347 *)
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Jeffrey Shallit, May 02 2016
STATUS
approved