50984

Appears in sequences

• Number of self-avoiding closed walks from 0 of area n in strip Z X {-1,0,1}.at n=13A038578
• G.f.: (2*x+4*x^2+4*x^3+4*x^4+2*x^5)/((1-x)^2*(1-x^2)^3*(1-x^3)^4*(1-x^4)).at n=16A127790
• Number of 4X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 4 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=41A192703