54801

Appears in sequences

• a(n) = (A000522(2*n) + 1)/2.at n=4A086894
• Number of simple graphs on n labeled nodes, where each maximally connected subgraph consists of a single node or has a unique cycle of length 3; also row sums of A144207.at n=7A144208
• Triangle T(n,k), n>=3, 3<=k<=n, read by rows: T(n,k) = number of simple graphs on n labeled nodes, where each maximally connected subgraph consists of a single node or has a unique cycle of length k.at n=10A144212
• Fill an infinite square array by following a spiral around the origin; in the central cell enter a(0)=1; thereafter, in the n-th cell, enter the sum of the entries of those earlier cells that can be seen from that cell.at n=19A280027
• Number of partitions of prime(n) into squares.at n=48A379551