135168

Appears in sequences

• a(n) = binomial(n,2) * 2^(n-1).at n=12A001815
• Theta series of 12-dimensional unimodular lattice {D_12}^{+}.at n=7A004533
• Duplicate of A004533.at n=7A014745
• Triangle read by rows: T(n,k) = number of paths of n upsteps U and n downsteps D that contain k UUDs.at n=43A051288
• A hierarchical sequence (S(W'2{3}*c) - see A059126).at n=10A059162
• 14-almost primes (generalization of semiprimes).at n=15A069275
• Replace 0 with 0000 in binary representation of n.at n=39A084473
• Row sums of triangle A118438.at n=12A118440
• Triangle T, read by rows, where T(n,k) = [T^(2^k)](n-k,0) * (2^k)^(n-k) for n>=k>=0 such that row n of the 2^(n-1)-th root of T consists solely of integers given by: [T^( 1/2^(n-1) )](n,k) = (2^k)^(n-k) for n>=0.at n=25A134049
• Triangular sequence from a Pidduck polynomials expansion: p(t) = (t/(1 - t))*((1 + t)/(1 - t))^x.at n=29A137394
• Second differences of even superperfect numbers A061652.at n=4A139236
• Second differences of Mersenne numbers A001348, divided by 2.at n=5A139242
• Number of 2 X 2 matrices having all terms in {1,...,n} and determinant = 0 (mod 3).at n=23A210698
• Number of 2 X 2 matrices having all elements in {0,1,...,n} and determinant = 0 (mod 3).at n=23A211033
• Number of (w,x,y,z) with all terms in {0,...,n}, and w, x and y odd.at n=32A212763
• a(n) = 4^n * A000108(n+1).at n=5A269796
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 838", based on the 5-celled von Neumann neighborhood.at n=17A290547
• Number of centrally symmetric diagonal Latin squares of order n with the first row in ascending order.at n=7A293777
• a(n) is the number of subsets of {1,2,...,n} that contain exactly two odd numbers.at n=22A330592
• Numbers k such that whenever the sum of three squares is divisible by k, at least two of the squares are congruent mod k.at n=54A354620