74801

Appears in sequences

• a(n) = n^4 + 2*n^3 + 4*n^2 + 3*n + 1 = ((n+1)^5+n^5) / (2*n+1).at n=16A072025
• Numbers y such that 19*y^2 + 81 is a square.at n=9A167709
• Subsequence of A167709 whose indices are congruent to 4 mod 5, i.e., a(n) = A167709(5*n+4).at n=1A167825
• a(n) is the number of 5 element sets of distinct integer-sided trapezoids whose base angles are 60 degrees that fill an equilateral triangular grid of side n units formed by directly binary space partitioning 3-trapezoid sets without forming 4-trapezoid sets.at n=51A391203