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A073547
Numbers k such that antid(k) = antid(k+1), where antid(k) = A066272(k).
1
1, 3, 8, 10, 14, 19, 20, 22, 27, 29, 40, 42, 46, 49, 52, 58, 65, 70, 74, 75, 82, 87, 90, 91, 94, 102, 103, 112, 116, 118, 122, 124, 131, 135, 148, 149, 151, 154, 157, 159, 171, 180, 183, 187, 188, 198, 204, 205, 208, 212, 213, 214, 217, 220, 222, 227, 231, 232
OFFSET
1,2
LINKS
MAPLE
N:= 1000: # to get all terms <= N-1
V:= Vector(N):
for k from 1 to floor(N/3) do
R1:= [seq(i, i=3*k .. N, 2*k)];
V[R1]:= map(`+`, V[R1], 1);
R2:= [seq(i, i=3*k+1 .. N, 2*k+1)];
V[R2]:= map(`+`, V[R2], 1);
R3:= [seq(i, i=3*k+2 .. N, 2*k+1)];
V[R3]:= map(`+`, V[R3], 1);
od:
select(t -> V[t]=V[t+1], [$1..N-1]); # Robert Israel, Sep 26 2016
MATHEMATICA
at[n_] := Count[Flatten[Quotient[#, Rest[Select[Divisors[#], OddQ]]] & /@ (2 n + Range[-1, 1])], Except[1]]; Select[Range[232], at[#] == at[# + 1] &] (* Jayanta Basu, Jul 01 2013 *)
CROSSREFS
Cf. A066272.
Sequence in context: A126581 A003038 A184870 * A047356 A083246 A023492
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Aug 31 2002
STATUS
approved