21592

Appears in sequences

• Indices of primes in sequence defined by A(0) = 89, A(n) = 10*A(n-1) - 21 for n > 0.at n=13A101075
• Half the difference between the larger and smaller term of the n-th amicable pair.at n=25A162884
• G.f.: Product_{n>=0} 1/(1-a(n)*x^(n+1))^3 = Sum_{n>=0} a(n)*x^n.at n=6A203507
• Expansion of (G(-x) / chi(-x))^2 in powers of x where chi() is a Ramanujan theta function and G() is a Rogers-Ramanujan function.at n=31A261866
• Half the difference between the larger and smaller terms of the n-th amicable pair (x,y) given in A259933.at n=25A275470
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 185", based on the 5-celled von Neumann neighborhood.at n=14A279700
• Number of (unlabeled) rooted trees with n leaf nodes and without unary nodes or outdegrees larger than six.at n=12A292212
• G.f.: Sum_{k>=1} x^(2*k)/(1+x^(2*k)) * Product_{k>=1} (1+x^k)/(1-x^k).at n=24A305122
• Sums of antidiagonals of A321964.at n=7A321961
• G.f. A(x) = Product_{n>=1} P(n,x), where P(1,x) = 1/sqrt(1 - 4*x), and P(n+1,x) = 1/sqrt(1 - 4*x + 4*x*P(n,x)) for n >= 1.at n=9A351512