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A086337
Numbers n such that n, n-1 and n-2 have the same prime signature.
1
35, 87, 95, 143, 203, 215, 219, 303, 395, 447, 635, 699, 923, 1043, 1139, 1263, 1311, 1347, 1403, 1643, 1763, 1839, 1887, 1895, 1943, 1983, 2015, 2103, 2183, 2219, 2307, 2363, 2435, 2463, 2519, 2643, 2667, 2723, 2735, 3099, 3387, 3603, 3695, 3731, 3867
OFFSET
1,1
LINKS
MATHEMATICA
sig[n_] := If[n == 1, {}, Last /@ FactorInteger[n]]; Select[Range[3902], sig[#] == sig[# - 1] == sig[# - 2] &] (* Giovanni Resta, Aug 14 2017 *)
CROSSREFS
Cf. A083793.
Sequence in context: A119691 A220007 A115393 * A118631 A347140 A220041
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Sep 01 2003
STATUS
approved