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%I #3 Mar 30 2012 17:37:51
%S 0,0,0,1,1,2,3,4,7,8,13,13,22,22,33,33,50,45,70,65,92,87,125,111,160,
%T 145,196,184,252,215,308,278,359,330,440,385,525,464,593,546,715,606,
%U 825,735,905,832,1078,926,1219,1065,1328,1223,1547,1310,1715,1529,1855
%N Number of 4-tuples of integers with GCD=1 and giving the lengths of sides of a nondegenerate quadrilateral with perimeter n.
%F Moebius transform of A057886.
%e There are five quadrilaterals with perimeter 8, with sides (1,1,3,3), (1,2,2,3), (1,2,3,2), (1,3,1,3) and (2,2,2,2). (2,2,2,2) is omitted since it has GCD=2, so a(8)=4.
%Y Cf. A051493.
%K nonn
%O 1,6
%A _John W. Layman_, Sep 19 2000
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