19516

Appears in sequences

• Representation degeneracies for boson strings.at n=31A005294
• a(n) = dot_product(1,2,...,n)*(7,8,...,n,1,2,3,4,5,6).at n=34A026049
• Even numbers (not equal to 2) to the left of the central elements of the (2,3)-Pascal triangle A029600.at n=29A029613
• Even numbers to right of central numbers of the (3,2)-Pascal triangle A029618.at n=47A029627
• Numbers whose base-4 representation contains exactly four 0's and three 3's.at n=27A045084
• Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2); sequence gives values of u1.at n=39A048189
• Given the infinite continued fraction (1+i)+((1+i)/(1+i)+((1+i)/((1+i)+...)))), where i is the square root of (-1), this is the numerator of the imaginary part of the convergents.at n=10A093726
• Triangle T(n, d) = the number of isomorphism classes of smooth Fano d-polytopes with n vertices, read by rows (n >= 2, 1 <= d < n).at n=61A127709
• a(n) = (n-1)*n*(n+1)*(n+2)*(2n+11)/120.at n=14A130857
• Positive numbers of the form x^4 - 6 * x^2 * y^2 + y^4 (where x,y are integers).at n=38A135789
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 0, -1), (0, 1, 1), (1, 0, 0)}.at n=8A150163
• Arises in classification of base sequences.at n=25A173061
• Number of 3-step left-handed knight's tours (moves only out two, left one) on an n X n board summed over all starting positions.at n=42A187173
• Number of partitions of n such that the number of parts is not divisible by the greatest part.at n=36A200727
• The Hwang-Deutsch function f_4(n).at n=47A260997
• Number of tiles in distance d from a given heptagon in the truncated order-3 tiling of the heptagonal plane (a.k.a. the "hyperbolic soccerball").at n=15A290398
• a(n) = 2*(a(n-1)+a(n-2)+a(n-3))-a(n-4) for n >= 4, with initial terms 0,0,1,1.at n=12A317974
• Number of ways to choose an integer partition of each factor in a factorization of n.at n=35A318948
• Number of irreducible conic curves containing 6 points of a cyclic order n-torsion subgroup of an elliptic curve.at n=23A379920