21622

Appears in sequences

• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, 1, 1), (0, 0, 1), (1, 0, 0), (1, 1, -1)}.at n=8A150156
• Number of Honaker primes (A033548) less than 10^n.at n=6A151993
• Triangle of coefficients of polynomials v(n,x) jointly generated with A209141; see the Formula section.at n=50A209142
• Triangle of coefficients of polynomials v(n,x) jointly generated with A209745; see the Formula section.at n=49A209746
• Number of (n+1)X(n+1) -9..9 symmetric matrices with every 2X2 subblock having sum zero and two or three distinct values.at n=6A211552
• Number of (w,x,y) with all terms in {0,...,n} and w<=x+y and x<=y.at n=36A212983
• a(n) = (n + 1)*(20*n^2 + 19*n + 6)/6.at n=18A220084
• Partial sums of A219661.at n=8A226061
• Numbers k(n) used for Markoff forms determining quadratic irrationals with purely periodic continued fractions.at n=20A305311