19250

Appears in sequences

• Number of exterior points formed by extending diagonals of n-gon in general position.at n=19A005701
• Dodecahedral surface numbers: a(0)=0, a(1)=1, a(2)=20, thereafter 2*((3*n-7)^2 + 21).at n=35A007589
• sec(arcsin(x)*exp(x))=1+1/2!*x^2+6/3!*x^3+33/4!*x^4+220/5!*x^5...at n=7A012326
• A convolution triangle of numbers obtained from A034687.at n=11A049375
• Number of scalars which can be constructed from the Riemann tensor and metric tensor in n dimensions.at n=21A050297
• Number of points in N^9 of norm <= n.at n=4A055408
• Number of points in N^n of norm <= 4.at n=9A055419
• a(n) = n*(n-1)*(n-2)*(n+3)/12.at n=22A117662
• Number of binary strings of length n with equal numbers of 00101 and 10110 substrings.at n=15A164250
• Triangle read by rows, A084938 * A165489 diagonalized as an infinite lower triangular matrix.at n=52A165490
• Integer areas of the intangents triangle of integer-sided triangles.at n=6A231740
• Let x(0)x(1)x(2)... x(q) denote the decimal expansion of n. Sequence lists the numbers n such that the suffix of decimal expansion x(2)... x(q) is the p-th divisor of n where p is the prefix of decimal expansion x(0)x(1).at n=8A234315
• Numbers with the property that in their factorization over distinct terms of A050376, the sums of prime and nonprime terms of A050376 are equal.at n=21A241270
• Least k formed by the concatenation of two numbers n and d such that d is the n-th divisor of k, or 0 if no such k exists.at n=18A257491
• Numbers m such that the concatenation of k and the k-th divisor of m is equal to m for some k.at n=18A258738
• Triangle of coefficients c(n,i), 1<=i<=n, such that for each n>=2, c(n,i) are setwise coprime; and for all primes p>2n-1, the sum of (-1)^i*c(n,i)*binomial(i*p,p) is divisible by p^(2n-1).at n=23A268512
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 310", based on the 5-celled von Neumann neighborhood.at n=36A271198
• Numbers n such that A279513(n) is a primorial number (A002110).at n=35A284889
• Harary index of the n X n white bishop graph.at n=21A296200
• Number of nonisomorphic proper colorings of partition multicycle graph using five colors.at n=81A298265