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6*a(n) are the perimeters of distinct triangles with integer sides i <= j <= k, whose area equals 4 times their perimeter. Terms occurring more than once belong to different triangles.
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%I #5 Mar 02 2020 18:53:51

%S 14,15,16,18,19,20,22,24,26,28,28,30,35,35,35,40,44,49,50,51,54,66,70,

%T 81,86,87,91,97,105,114,119,119,135,154,185,187,204,219,275,322,385,

%U 390,391,737,1430

%N 6*a(n) are the perimeters of distinct triangles with integer sides i <= j <= k, whose area equals 4 times their perimeter. Terms occurring more than once belong to different triangles.

%C There are 45 integer-sided triangles with 4*area = perimeter, with terms 28 and 119 corresponding to pairs, and terms 35 to a triple of such triangles with different sides.

%Y The 41 terms of A289220, divided by 24, are all terms of this sequence, but omitting distinct triangles with identical perimeters.

%K nonn,fini,full

%O 1,1

%A _Hugo Pfoertner_, Mar 02 2020