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%I #12 Jul 23 2023 18:23:36
%S 2,2,7,13,44,95,231
%N Length of row n of the irregular triangle A364312.
%C This gives the total number a(n) of nonnegative coefficients of the integer polynomials of degree k = 1, 2, ..., n-1 of Cantor's height n, for n >= 2, and for n = 1 the degree is k = 1, with polynomial 1*x.
%C Not all rows of A364312 have entries for k = n-1, e.g., for n = 4 the k = 3 entry [1, 0, 0, 1] is not recorded because both x^3 + 1 and the signed version x^3 - 1 factorize. Similar cases appear for n = 6 and n = 7.
%e a(3) = 7 because row n = 3 of A364312 is 2, 1, 1, 2, 1, 0, 1, from [2, 1], [1, 2]; [1, 0, 1] for the polynomials 2*x + 1, x + 2, x^2 + 1.
%Y Cf. A364312.
%K nonn,more
%O 1,1
%A _Wolfdieter Lang_, Jul 19 2023