39680

Appears in sequences

• Theta series of D*_32 lattice.at n=3A022085
• a(0)=0, a(n) = n*E(2n-1) for n >= 1, where E(n) = A000111(n) are the Euler (or up-down) numbers.at n=5A024255
• Number of points of l_1 norm n in the "diamond" lattice D^+_4.at n=31A035878
• Triangle read by rows: T(n,k) (n >= 2, 0 <= k <= n) = number of over-all crude totals of unbranched k-5-catapolyheptagons.at n=37A038195
• Expansion of ((1-x)/(1-2*x))^4.at n=10A062109
• Triangle T(n,k) read by rows; related to number of preorders.at n=24A079507
• Binomial transform of positive cubes.at n=8A084903
• An Euler triangle.at n=16A117414
• If X_1, ..., X_n is a partition of a 2n-set X into 2-blocks then a(n) is equal to the number of 3-subsets of X containing none of X_i, (i=1,...,n).at n=29A130809
• Irregular triangle, T(n, k) = coefficients of p(x, n), where p(x, n) = (1-2*x)^(n+1) * Sum_{j>=0} j^n*(x/(1-x))^j, read by rows.at n=49A142073
• Number of ways to place 5 nonattacking bishops on an n X n board.at n=5A172129
• Numbers of the form p^8*q*r where p, q, and r are distinct primes.at n=25A179747
• Sum_{0<j<k<=n} s(k)-s(j), where s(j)=A002620(j) is the j-th quarter-square.at n=29A206806
• Triangle of coefficients of polynomials v(n,x) jointly generated with A209143; see the Formula section.at n=51A209144
• Number of (w,x,y,z) with all terms in {1,...,n} and w>=2x and y>3z.at n=32A212522
• Number of (n+1) X (1+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=4A235251
• Number of (n+1) X (5+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=0A235255
• T(n,k) is the number of (n+1) X (k+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=10A235258
• T(n,k) is the number of (n+1) X (k+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 7, with no adjacent elements equal (constant-stress tilted 1 X 1 tilings).at n=14A235258
• Number of times prime(n) occurs as the least prime factor among numbers 1 .. prime(n)^4: a(n) = A078898(A030514(n)).at n=18A250478