28400

Appears in sequences

• Number of loopless tree-rooted planar maps with 4 vertices and n faces.at n=5A006429
• Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 21 (most significant digit on right).at n=20A029514
• Number of nonempty subsets of {1,2,...,n} in which exactly 3/4 of the elements are <= (n-4)/2.at n=24A048064
• Analog of A060410 for the 7x+1 problem (cf. A133421).at n=5A133426
• The sum of all the entries in an n X n Cayley table for multiplication in Z_n.at n=39A160255
• a(n) = 2*n*A071148(n).at n=19A177082
• Number of (n+1) X (3+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=3A235234
• Number of (n+1) X (4+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=2A235235
• T(n,k) is the number of (n+1) X (k+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=17A235239
• T(n,k) is the number of (n+1) X (k+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=18A235239
• G.f.: 1/(1 - x^2/(1 - x^3/(1 - x^5/(1 - x^7/(1 - x^11/(1 - ... - x^prime(k)/(1 - ... ))))))), a continued fraction.at n=37A285407
• Sequence shifts left five places under Weigh transform with a(n) = signum(n) for n<5.at n=35A316077
• a(n) is the number of regular k-gons in three dimensions with all k vertices (x,y,z) in the set {1,2,...,n}^3.at n=8A338323
• Triangle read by rows: T(n,k) is the number of tree-rooted loopless planar maps with n edges, k faces and no isthmuses, n >= 0, k = 1..n+1.at n=39A342985
• Triangle read by rows: T(n,k) is the number of tree-rooted loopless planar maps with n edges, k faces and no isthmuses, n >= 0, k = 1..n+1.at n=41A342985
• Number of cells in a regular 7-gon after n generations of mitosis.at n=28A349808
• a(n) = n^2 * prime(n).at n=19A356868
• G.f. A(x) satisfies A(x) = 1 / (1 - x - x * A(x^4)).at n=14A367660