87550

Appears in sequences

• Number of 2-element intersecting families (with not necessarily distinct sets) whose union is an n-element set.at n=10A053156
• Number of regions in regular n-gon which are quadrilaterals (4-gons) when all its diagonals are drawn.at n=46A067151
• Number of 4-ary Lyndon words of length n over GF(4) with trace 0 and subtrace 0.at n=11A074446
• Number of one-element transitions among partitions of the integer n for labeled parts.at n=23A094533