6007320

Appears in sequences

• a(n) = A000166(n)*binomial(n+1,2).at n=9A065087
• Triangle read by rows: T(n,k) is the number of permutations of [n] starting with 1, having no 3-sequences and having k successions (0 <= k <= floor(n/2)); a succession of a permutation p is a position i such that p(i +1) - p(i) = 1.at n=44A180186