18784

Appears in sequences

• Number of achiral rooted trees.at n=27A003241
• Denominators of continued fraction convergents to sqrt(282).at n=10A041531
• Numbers k such that h(k) = h(k-1) + h(k-2), where h(k) = A006577(k) + 1 is the length of the sequence {k, f(k), f(f(k)), ...., 1} in the Collatz (or 3x + 1) problem. (The earliest "1" is meant.)at n=34A078418
• Numbers n such that h(n) = 2 h(n-1) where h(n) is the length of the sequence {n, f(n), f(f(n)), ...., 1} in the Collatz (or 3x + 1) problem. (The earliest "1" is meant.)at n=38A078419
• Number (undirected) Hamiltonian paths in the 5 X n knight graph.at n=5A083386
• Integers n such that 2*10^n + 81 is a prime number.at n=17A110920
• Self-convolution 8th power equals A113668, where a(n) = n*A113668(n-1) for n>=1, with a(0)=1.at n=4A113674
• Coefficients of a generalized Jaco-Lucas polynomial (even indices) read by rows.at n=39A122076
• a(1)=0, a(n) = n^3 - a(n-1).at n=32A153026
• Average number of round trips of length n on the Laguerre graph L_4.at n=5A199579
• Triangle version of the array w(N,L) of the average number of round trips of length L on Laguerre graphs L_N.at n=39A201198
• Number of (w,x,y,z) with all terms in {1,...,n} and w+x=|x-y|+|y-z|.at n=33A212676
• Number of (n+1) X (1+1) 0..2 arrays colored with the sum of the maximum and minimum values of each 2 X 2 subblock.at n=4A236011
• Number of (n+1)X(5+1) 0..2 arrays colored with the sum of the maximum and minimum values of each 2X2 subblock.at n=0A236015
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays colored with the sum of the maximum and minimum values of each 2X2 subblock.at n=10A236018
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays colored with the sum of the maximum and minimum values of each 2X2 subblock.at n=14A236018
• E.g.f.: exp(4*x*G(x)^3) / G(x)^3 where G(x) = 1 + x*G(x)^4 is the g.f. of A002293.at n=5A251574
• Table of coefficients in functions R(n,x) defined by R(n,x) = exp( n*x*G(n,x)^(n-1) ) / G(n,x)^(n-1) where G(n,x) = 1 + x*G(n,x)^n, for rows n>=1.at n=41A251660
• Composites whose prime factorization in base 3 is an anagram of the number in base 3.at n=33A260047
• Numbers k that end with ( sum of digits of k )^2.at n=28A270343