91881

Appears in sequences

• a(n) = 1^2 + 3^2 + 5^2 + 7^2 + ... + (2*n-1)^2 = n*(4*n^2 - 1)/3.at n=41A000447
• Odd tetrahedral numbers: a(n) = (4*n+1)*(4*n+2)*(4*n+3)/6.at n=20A015219
• Binomial coefficients C(n,80).at n=3A017744
• Binomial coefficients C(83,n).at n=3A017799
• a(n) = (prime(n) - 1)*(prime(n) - 3)*(prime(n) - 5)/48.at n=37A030004
• a(n) = binomial(prime(n+2), 3).at n=21A126995
• 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, 0), (-1, 0, -1), (1, -1, 1), (1, 1, -1), (1, 1, 1)}.at n=9A149627
• Sequence related to Hankel transform of super-ballot numbers.at n=39A156126
• a(n) = binomial(3*n+2,3).at n=26A228888
• Array a(n,m) read by descending antidiagonals giving the number of intervals in a generalized Tamari lattice of m-ballot paths of size n.at n=32A255918
• Number of 4-member subsets of [4*n] whose elements sum to a multiple of n.at n=21A318625
• Tetrahedral numbers that are not divisible by any smaller tetrahedral number except 1.at n=21A318701