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A076034
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Group the natural numbers so that the n-th group contains the smallest set of n relatively prime numbers: (1), (2, 3), (4, 5, 7), (6, 11, 13, 17), (8, 9, 19, 23, 25), (10, 21, 29, 31, 37, 41), ...
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4
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1, 2, 3, 4, 5, 7, 6, 11, 13, 17, 8, 9, 19, 23, 25, 10, 21, 29, 31, 37, 41, 12, 35, 43, 47, 53, 59, 61, 14, 15, 67, 71, 73, 79, 83, 89, 16, 27, 49, 55, 97, 101, 103, 107, 109, 18, 65, 77, 113, 127, 131, 137, 139, 149, 151, 20, 33, 91, 157, 163, 167, 173, 179, 181, 191, 193
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OFFSET
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1,2
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LINKS
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EXAMPLE
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1; 2,3; 4,5,7; 6,11,13,17; 8,9,19,23,25; 10,21,29,31,37,41; ...
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MAPLE
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S:=[$1..1000]: Res:= NULL:
for n from 1 to 20 do
A:= [S[1]]; R:= 1; count:= 1;
for k from 2 while count < n do
if andmap(t -> igcd(t, S[k])=1, A) then count:= count+1; A:= [op(A), S[k]]; R:= R, k; fi
od;
S:= subsop(op(map(t -> t=NULL, [R])), S);
Res:= Res, op(A);
od:
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PROG
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(Perl) See Links section.
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CROSSREFS
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KEYWORD
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AUTHOR
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EXTENSIONS
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Crossrefs added by Paul Tek, Oct 24 2015
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STATUS
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approved
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