

A113458


Least k such that k, k+n and k+2n have the same prime signature.


3



33, 3, 155, 3, 77, 5, 51, 3, 77, 3, 35, 5, 50, 3, 187, 6, 21, 5, 39, 3, 145, 33, 39, 5, 69, 39, 91, 3, 33, 7, 15, 12, 221, 3, 28, 7, 21, 3, 55, 3, 33, 5, 91, 66, 209, 69, 35, 5, 50, 3, 115, 39, 141, 5, 51, 6, 145, 85, 15, 7, 21, 93, 95, 3, 57, 5, 51, 3, 65, 15, 35, 7, 69, 55, 287, 6
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OFFSET

1,1


COMMENTS

Third row of A113456.


LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..20000


EXAMPLE

a(4) = 3 because 3, 7 and 11 have the same prime signature.


MAPLE

s:= n> sort(map(i> i[2], ifactors(n)[2])):
a:= proc(n) option remember; local k; for k
while s(k)<>s(k+n) or s(k)<>s(k+2*n) do od; k
end:
seq(a(n), n=1..100); # Alois P. Heinz, Feb 28 2018


CROSSREFS

Cf. A052214, A113456, A113467.
Sequence in context: A032445 A135088 A113467 * A120584 A236177 A123173
Adjacent sequences: A113455 A113456 A113457 * A113459 A113460 A113461


KEYWORD

easy,nonn


AUTHOR

David Wasserman, Jan 08 2006


STATUS

approved



