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%I #5 Jan 11 2020 15:39:43
%S 0,0,3,7,12,15,32,35,55,63,95,119,135,224,231,255,320,351,455,495,855,
%T 864,896,1071,1440
%N a(n) = 4 * squared radius of inscribed circles of triangles with integer sides i <= j <= k, such that the number of triangles with this radius sets a new record. If this radius is not a multiple of (1/4), a(n) = 0.
%C It is conjectured that all radii of incircles leading to records with the exception of the first two terms are multiples of 1/4, thus a(n) > 0 for all n > 2.
%C See A331040 for more information and examples.
%F If A331041(n) equals 1 or 4, a(n) = 4 * A331040(n)/A331041(n), 0 otherwise.
%Y Cf. A120062, A331012.
%Y Cf. A331040, A331041, A331043 (records of numbers of triangles).
%K nonn,more
%O 1,3
%A _Hugo Pfoertner_, Jan 11 2020