106821

Appears in sequences

• Partial sums of Chebyshev sequence S(n,10) = U(n,5) = A004189(n+1).at n=5A097784
• Number of 2 X 2 matrices having all terms in {-n,...,0,...,n} and 0 <= determinant <= n.at n=18A211146
• Number of compositions of n with exactly one part equal to 1 or exactly one part equal to 2.at n=20A238159