50380

Appears in sequences

• Number of discordant permutations.at n=6A000563
• a(n) = (n+1)*(5*n^2+4*n+1).at n=21A027849
• Values of n for which pi_{4,3}(p_n) - pi_{4,1}(p_n) = -1, where p_n is the n-th prime and pi_{m,a}(x) is the number of primes <= x which are congruent to a (mod m).at n=2A051024
• Let f(x) = phi(x) + sigma(x); a(n) = least k such that at k begins a maximal run of length n of consecutive strict local extrema of f, or 0 if no such k exists.at n=40A066923
• Integers k for which {prime(1), prime(2), ..., prime(k)} (mod 4) is biased towards 1.at n=2A096628
• Number of unlabeled balanced rooted semi-identity trees with 2n-1 nodes and depth n.at n=24A306274
• T(n,k) is the number of length-n weak ascent sequences (prefixed with a zero) with k weak ascents, triangle read by rows.at n=53A369321
• a(n) is the number of distinct five-cuboid combinations filling n X n X n cube without allowing a cut spanning through the full cube in any of filling positions.at n=30A384743