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A273062
Discriminator of the composite numbers A002808.
2
1, 3, 3, 6, 7, 7, 7, 12, 13, 13, 13, 18, 19, 19, 22, 23, 24, 25, 25, 25, 30, 31, 32, 33, 33, 36, 37, 37, 37, 42, 43, 43, 46, 47, 48, 49, 49, 52, 53, 54, 55, 55, 55, 60, 61, 62, 63, 63, 66, 67, 67, 67, 72, 73, 74, 75, 75, 78, 79, 79, 82, 83, 84, 85, 85, 88, 89, 90, 91, 92, 93, 93, 96, 97, 97, 97, 102, 103, 103, 103, 108, 109, 109, 112, 113
OFFSET
1,2
COMMENTS
The discriminator of a sequence is the least integer k such that the first n terms are pairwise incongruent, modulo k.
LINKS
MAPLE
R:= 1: y:= 1: C:= remove(isprime, [$1..200]):
for n from 2 to nops(C) do
do
S:= convert(C[1..n] mod y, set);
if nops(S) = n then break fi;
y:= y+1;
od;
R:= R, y;
od:
R; # Robert Israel, Jul 13 2023
CROSSREFS
Cf. A002808.
Sequence in context: A016652 A008867 A185958 * A269170 A003879 A376821
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, May 14 2016
STATUS
approved