1681680

Appears in sequences

• a(n) = 28*(n+1)*binomial(n+3,8)/3.at n=8A027793
• a(n) = 15*(n+1)*binomial(n+3,10).at n=6A027795
• a(n) = binomial(2n+4,n)*binomial(n+4,4).at n=6A106440
• Product of the numbers k in the range 1 <= k <= n such that the proper divisors of k are a subset of the proper divisors of n.at n=13A158977
• Triangle read by rows: T(n,k) is the number of tree-rooted planar maps with n edges and k+1 faces, n >= 0, k = 0..n.at n=39A342982
• Triangle read by rows: T(n,k) is the number of tree-rooted planar maps with n edges and k+1 faces, n >= 0, k = 0..n.at n=41A342982
• Positions of records in A227872, i.e., integers whose number of odious divisors sets a new record.at n=35A355969
• Numbers k with record values of the ratio A000005(k)/A246600(k) between the total number of divisors of k and the number of divisors d of k such that the bitwise OR of k and d is equal to k.at n=28A361937
• Terms of A363690 with a record number of divisors.at n=29A363692
• a(n) = smallest prime(n)-smooth number k such that r(k) >= r(P(n+1)), where r(n) = A010846(n) and P(n) = A002110(n).at n=5A363794
• a(n) = A372723(2*n, n).at n=4A372716
• Triangle read by rows: Column k has e.g.f. t^k / ((1 - t)^(k + 1) * exp(t)).at n=40A372723