3445032

Appears in sequences

• Number of essentially different ways of arranging numbers 1 through 2n around a circle so that the sum of each pair of adjacent numbers is prime and the odd (or even) numbers are in order.at n=26A072616
• Number of permutations of [n] that avoid the shuffle pattern s-k-t, where s = 123 and t = 123.at n=10A324137