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A131857 Numbers m such that A131852(m) = 1. 8
2, 3, 6, 7, 18, 19, 22, 23, 32, 33, 36, 37, 42, 43, 46, 47, 48, 49, 52, 53, 58, 59, 62, 63, 66, 67, 70, 71, 82, 83, 86, 87, 96, 97, 100, 101, 106, 107, 110, 111, 112, 113, 116, 117, 122, 123, 126, 127, 162, 163, 166, 167, 178, 179, 182, 183, 226, 227, 230, 231, 242, 243 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MAPLE
Z:= proc(n) option remember;
I*procname(floor(n/2))+(n mod 2)
end proc:
Z(0):= 0:
select(Im@Z=1, [$0..1000]); # Robert Israel, Dec 18 2017
MATHEMATICA
z[0] = 0; z[n_] := z[n] = z[Floor[n/2]]*I + Mod[n, 2]; Select[Range[0, 250], Im[z[#]] == 1&] (* Jean-François Alcover, Jan 31 2018 *)
PROG
(PARI) isok(n) = {d = Vecrev(binary(n)); imag(sum(k=1, #d, d[k]*I^(k-1))) == 1; } \\ Michel Marcus, Jan 31 2018
CROSSREFS
Sequence in context: A052487 A067951 A131862 * A064970 A064292 A079663
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 22 2007
STATUS
approved

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Last modified August 10 09:30 EDT 2024. Contains 375044 sequences. (Running on oeis4.)