39858

Appears in sequences

• Base-9 palindromes that start with 6.at n=26A043033
• Number of ways to place 3 nonattacking kings on a 3 X n board.at n=22A172202
• a(n) = floor((1 + 3^n)/(1 + 3*n)).at n=12A191634
• The Wiener index of the dendrimer D_n defined pictorially in Fig. 1 of the Heydari et al. reference.at n=4A227708
• Sequence defined by a(1)=a(2)=1 and a(n) = gray(gray(a(n-1)) + gray(a(n-2))), with gray(m) = A003188(m).at n=31A265386
• a(n) = Sum_{k=0..(n-1)/2} (n+2-k)*binomial(n-1-k,k).at n=18A271785
• Composite numbers k such that P(k, 7) == 7 (mod k), where P(k, 7) = A084768(k) is the k-th Legendre polynomial evaluated at 7.at n=21A330205
• Triangle read by rows: T(n,k) is the number of planar tanglegrams of size n with irreducible component of size k.at n=41A371659
• a(n) = (A084218(n) - 1)/12.at n=26A373040