134844

Appears in sequences

• Number of 3 X n binary matrices such that any 2 rows have a common 1, up to column permutations.at n=15A052387
• 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), (0, 1, 1), (1, 0, -1), (1, 0, 0)}.at n=9A150279
• a(n) = 2025*n^2 - 3401*n + 1428.at n=8A156854
• G.f.: exp( Sum_{n>=1} 2*sigma(n*4^n)*x^n/n ).at n=5A193103
• a(n)/A002939(n+1) is the Kirchhoff index of the join of the disjoint union of two complete graphs on n vertices with the empty graph on n+1 vertices.at n=19A338109