234064

Appears in sequences

• Number of subsets of {1, ..., n} that are not double-free.at n=18A088808
• Number of 4-step king's tours on an n X n board summed over all starting positions.at n=26A186863
• Number of numbers k in interval [(p_n)^2+1, (p_n)^4] for which lpf(k-3)>lpf(k-1)>=p_n, where p_n=prime(n) and lpf = A020639.at n=18A243803