79695

Appears in sequences

• Numerator of n*(n-2)*(2*n-1)/(2*(n-1)).at n=33A022997
• a(n) = 9*binomial(n,4) = 3*n*(n-1)*(n-2)*(n-3)/8.at n=23A060008
• Numbers k such that phi(5k+1) = sigma(k).at n=2A067226
• a(n) = n * [1 + sum(k=1 to n) prime(k)].at n=35A083725
• Numbers k such that both k and k+1 are abundant.at n=18A096399
• Triangle read by rows: T(n,k) is the number of noncrossing trees with n edges in which the leftmost child of the root has degree k.at n=49A101401
• Numbers k such that both sigma(k) >= 2*k-1 and sigma(k+1) >= 2*(k+1)-1.at n=20A103289
• Denominators of the squarefree totient analogs of the harmonic numbers F_n.at n=46A138317
• Denominators of the squarefree totient analogs of the harmonic numbers F_n.at n=47A138317
• Numbers k such that k-4, k-2, k+2 and k+4 are prime.at n=32A173037
• a(n) is the smallest k > n such that psi(k) is the arithmetic mean of psi(k - n) and psi(k + n), or 0 if no such k exists.at n=8A292307
• p-INVERT of the odd positive integers, where p(S) = 1 - S^3.at n=11A292481
• Numbers k such that both k and k+1 are Zumkeller numbers (A083207).at n=16A328327
• Table read by rows. Interpolating the swinging factorial (A056040) and the double factorial (A001147).at n=25A350464
• Let G_n denote the planar graph defined in A358746 with the addition, if n is odd, of the circle containing the initial n points; sequence gives the number of edges in G_n.at n=22A370977
• Denominators of the partial sums of the reciprocals of the alternating sum of divisors function (A206369).at n=46A379620
• Numbers k with a record number of proper divisors, where all of them have binary weights that are different from the binary weight of k.at n=14A383365
• Numbers k such that each of k and k+1 is either a practical number (A005153) or an almost practical number (A174533).at n=14A387654