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%I #7 Jan 06 2024 01:38:05
%S 1,1,1,1,2,0,2,2,0,2,1,2,1,2,0,1,4,0,2,0,1,3,2,0,2,2,0,2,1,2,1,4,0,0,
%T 2,0,3,2,2,2,0,0,3,2,0,1,4,0,2,2,0,4,0,0,0,3,3,2,2,0,2,2,0,0,2,2,3,2,
%U 0,2,2,0,3,2,0,0,4,0,1,2
%N Number of compositions (ordered partitions) of n into at most 2 triangular numbers.
%F a(n) = c(n) + Sum_{k=1..n-1} c(k) * c(n-k), where c = A010054. - _Wesley Ivan Hurt_, Jan 06 2024
%Y Cf. A000217, A010054, A023361, A053603, A347731, A347732, A347733, A347734.
%K nonn,easy
%O 0,5
%A _Ilya Gutkovskiy_, Sep 11 2021