18544

Appears in sequences

• Number of labeled servers of dimension 19.at n=3A027406
• Number of nonisomorphic commutative groupoids with 1 idempotent.at n=3A030263
• Triangle read by rows: T(n,k) is the number of commutative groupoids with n elements and k idempotents.at n=11A038021
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+839)^2 = y^2.at n=7A130647
• 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, 0), (-1, -1, 1), (-1, 0, 1), (0, 0, -1), (1, 1, 0)}.at n=9A149128
• Number of (n+1)X(n+1) -5..5 symmetric matrices with every 2X2 subblock having sum zero and two or three distinct values.at n=8A211332
• Number of nondecreasing -3..3 vectors of length n whose dot product with some nondecreasing -3..3 vector equals n.at n=11A226406
• Numbers which are representable as a sum of nineteen but no fewer consecutive nonnegative integers.at n=19A270303
• Numbers k such that e(k) > 1 and k == e(k) (mod lambda(k)), where e(k) = A051903(k) is the maximal exponent in prime factorization of k.at n=17A327295
• Positions of 0's in A330314.at n=13A330325
• G.f. A(x) satisfies: (1 - x)/(1 + x) = Sum_{n=-oo..+oo} (-1)^n * A(x)^(n^2).at n=15A355151
• Number of integer partitions of n with a unique non-co-mode.at n=46A363129
• a(n) is the number of distinct ways to partition the set {1,2,...,n} into nonempty subsets such that the sum of the pi(x)*(pi(x) + 1)/2 values of each subset's size x equals n, where pi() is the prime counting function given by A000720.at n=17A364525