81856

Appears in sequences

• Triangular matrix T, read by rows, that satisfies: T = D + SHIFT_LEFT(T^3), where SHIFT_LEFT shifts each row 1 place to the left and D is the diagonal matrix {1, 2, 3, ...}.at n=6A107671
• Column 0 of triangle A107671.at n=3A107672
• Matrix cube of triangle A107671.at n=7A107676
• a(n) = 20*a(n-1) - 64*a(n-2) for n > 1; a(0) = 1, a(1) = 19.at n=4A166965
• a(n) = Sum_{1 <= x_1, x_2 <= n} gcd(x_1, x_2, n)^4.at n=15A372926