131544

Appears in sequences

• a(n) = floor(n*(n-1)*(n-2)*(n-3)/5).at n=30A011915
• Triangle read by rows: a(n, m) = S1(n, m)*3^(n-m), where S1 are the signed Stirling numbers of first kind A008275 (n >= 1, 1 <= m <= n).at n=23A051141
• Number of primitive (aperiodic) reversible strings with n beads using a maximum of four different colors.at n=8A056315
• Values of n*d(k)*sopf(k) associated with A134382.at n=28A134386
• Numbers k such that A003415(k) == A276085(k) (mod 5^5), where A003415 is the arithmetic derivative and A276085 is the primorial base log-function.at n=41A391865