19228

Appears in sequences

• Number of nonequivalent dissections of a polygon into n quadrilaterals by nonintersecting diagonals rooted at a cell up to rotation.at n=7A005033
• a(n) = floor(C(n,6)/7).at n=24A011797
• Number of necklaces with 7 black beads and n-7 white beads.at n=18A032192
• Starting from generation 8 add previous and next term yielding generation 9.at n=20A048455
• Coefficients of power series for (1 - (1-8*x)^(1/4))/2.at n=6A048779
• Numbers m such that 2*phi(m) = phi(m+1).at n=20A050472
• T(n,7), array T as in A051168; a count of Lyndon words; aperiodic necklaces with 7 black beads and n-7 white beads.at n=18A051172
• Number of independent components for a Weyl tensor in n dimensions.at n=19A052472
• a(n) = T(2*n+1, n), array T as in A054106.at n=8A054109
• (1/2)*(n^2+n+2)*(n^2+3*n+1).at n=13A058310
• Group the natural numbers such that the product of the terms of the n-th group is divisible by n!: (1), (2), (3, 4), (5, 6, 7, 8), (9, 10, 11, 12), (13, 14, 15, 16, 17, 18), (19, 20, 21, 22, 23, 24), ... Sequence contains the product of the terms of the n-th group divided by n!. a(n) = A085912(n)/(n!).at n=6A085915
• A002415 and A052472 interlaced.at n=42A117651
• a(n) = floor(n*(n+2)*(n+4)*(n-6)/192).at n=44A117652
• Heptagonal numbers A000566 which are the sum of two other heptagonal numbers > 0.at n=8A133251
• Number of ways to place 2 queens on an n X n chessboard so that they attack each other.at n=22A144945
• a(n) = (-1)^(n+1) * n*(n-1)*(n-4)*(n+1)/12.at n=21A167387
• a(n) = n*(10*n-3).at n=44A195018
• Triangle T(n,m) = coefficient of x^n in expansion of (1/2-1/2*(1-8*x)^1/4)^m = sum(n>=m, T(n,m) x^n), n>=1, m>=1.at n=21A202039
• Number of n X 4 arrays with each row a permutation of 1..4 having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order.at n=5A222002
• T(n,k)=Number of nXk arrays with each row a permutation of 1..k having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order.at n=41A222005