22260

Appears in sequences

• Rencontres numbers: number of permutations of [n] with exactly 3 fixed points.at n=6A000449
• Triangle T(n,k) of rencontres numbers (number of permutations of n elements with k fixed points).at n=48A008290
• Triangle of rencontres numbers.at n=31A008291
• Theta series of A_6 lattice.at n=23A008446
• Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DDR = Deca-dodecasil 3R[Si120O240]qR starting with a T6 atom.at n=13A019108
• a(n) = Sum_{0 <= i < j <= n} (prime(j) - prime(i))^2, where prime(0) = 1.at n=11A024526
• Star of David matchstick numbers: a(n) = 6*n*(3*n+1).at n=35A045946
• Triangle read by rows: T(n,k) = number of partial derangements, that is, the number of permutations of n distinct, ordered items in which exactly k of the items are in their natural ordered positions, for n >= 0, k = n, n-1, ..., 1, 0.at n=51A098825
• Least number k such that kn + 1 is a prime dividing prime(n)^n - 1.at n=34A191549
• Number of (w,x,y,z) with all terms in {1,...,n} and median<mean.at n=15A212135
• Partition array a(n,k) with the total number of necklaces (C_n symmetry) with n beads, each available in n colors, with color signature given by the k-th partition of n in Abramowitz-Stegun(A-St) order.at n=58A212360
• Denominators of rationals with e.g.f. D(4,x), a Debye function.at n=52A227574
• Indices of the start of 10 successive distinct digits in the decimal expansion of Pi.at n=10A258157
• Expansion of (eta(q^3)eta(q^6)/(eta(q)eta(q^2)))^4 in powers of q.at n=10A284607
• Least integer k such that the area of the triangle (prime(n), k, k+1) is an integer.at n=45A286328
• Areas of integer-sided triangles whose area equals 5 times their perimeter.at n=42A289221
• a(n) = 81*n^2 - 69*n + 24.at n=17A304616
• Triangular array, read by rows: T(n,k) = [(x*y*z)^k] (-1 + (1 + x + 1/x)*(1 + y + 1/y)*(1 + z + 1/z))^n for -n <= k <= n.at n=28A329819
• Triangular array, read by rows: T(n,k) = [(x*y*z)^k] (-1 + (1 + x + 1/x)*(1 + y + 1/y)*(1 + z + 1/z))^n for -n <= k <= n.at n=32A329819
• Number of Sós permutations of {0,1,...,n}.at n=40A330503