18012

Appears in sequences

• Tri-substituted alkanes of form C_n H_{2n-1} X_2 Y, or equivalently bi-substituted alkyls of form -C_n H_{2n-1} X_2 (n=1: CHXXY; n=2: CXXY-CHHH CXYH-CXHH CXXH-CYHH).at n=10A022014
• Triangle giving number of unbranched catapolytetragons, read by rows.at n=62A038766
• When squared gives number composed just of the digits 1, 2, 3, 4.at n=29A061677
• Number of base 6 circular n-digit numbers with adjacent digits differing by 3 or less.at n=6A125316
• (1, 3, 5, 7, 9, ...) convolved with (1, 0, 3, 5, 7, 9, ...).at n=30A179903
• Number of partitions of n^2 into positive cubes.at n=27A218495
• Sum of the largest parts in the partitions of 4n into 4 parts with smallest part = 1.at n=17A240711
• Number of partitions of n^3 into cubes.at n=9A259792
• Array read by antidiagonals upwards: T(n,k) = number of partitions of k^n into n-th powers (n>=1, k>=0).at n=75A259799
• Second largest coefficient among the polynomials in row n of the triangle of q-binomial coefficients.at n=18A277271
• a(n) = 12*n^2 + 18*n.at n=38A277980
• Array read by antidiagonals: T(m,n) = number of m-ary words of length n with cyclically adjacent elements differing by 3 or less.at n=38A285281
• Total number of isomers (nonisomorphic systems) of unbranched tri-4-catafusenes as a function of the number of hexagons (see Cyvin et al. (1996) for precise definition).at n=7A323941
• Irregular triangle read by rows giving the total number of isomers (nonisomorphic systems) of unbranched k-4-catafusenes.at n=55A323942
• Number of triangular regions into which a figure made up of a row of n adjacent congruent rectangles is divided upon drawing diagonals of all possible rectangles.at n=20A324042
• The number of vertices formed when every pair of n points, placed at the vertices of a regular n-gon, are connected by a circle and where the points lie at the ends of the circle's diameter.at n=17A358746