22086

Appears in sequences

• Define the sequence S(a(0),a(1)) by a(n+2) is the least integer such that a(n+2)/a(n+1) > a(n+1)/a(n) for n >= 0. This is S(5,20).at n=6A022021
• Number of directed site animals on hexagonal net (honeycomb) with n sites.at n=10A055919
• a(1) = 1; a(n) = least number such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.at n=4A061359
• a(n) is the (n+1)st (n+2)-gonal number.at n=35A064808
• a(1) = 0; for n > 1, a(n) is the smallest integer > 0 such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.at n=5A065691
• a(1) = 81; for n > 1, a(n) is the smallest integer > 0 such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.at n=3A065793
• Triangle read by rows where the n-th row is the first row of M^n, with M the (n+1)-by-(n+1) matrix with (3,1,3,1,3,1,...) on its main diagonal and (1,3,1,3,1,3,...) on its superdiagonal.at n=50A124573
• Number of reduced words of length n in Coxeter group on 3 generators S_i with relations (S_i)^2 = (S_i S_j)^7 = I.at n=14A164352
• 37-gonal numbers: a(n) = n*(35*n-33)/2.at n=36A282852
• Numbers k such that (86*10^k + 121)/9 is prime.at n=23A283185