19308

Appears in sequences

• a(0) = 1, a(1) = 4, and a(n) = a(n-1) + a(n-2) for n >= 2.at n=19A000285
• Numbers n such that n is a substring of its square in base 3 (written in base 10).at n=28A018827
• 5-digit terms in the continued fraction for Pi.at n=2A048960
• Number of 6k+1 primes (A002476) in range ]2^n,2^(n+1)].at n=18A095015
• Fibonacci sequence with initial values a(0) = 3 and a(1) = 1.at n=20A104449
• a(n) = prime(n)*prime(n+1)*prime(n+2) - prime(n+3)^2.at n=8A135734
• Number of compositions (p0, p1, p2, ...) of n with pi - p0 <= i and pi >= p0.at n=17A177510
• Coefficient array for the third power of the monic integer Chebyshev polynomials 2*T(2*n,x/2) as a function of x^2.at n=26A219236
• Values of x in the solutions to x^2 - 3xy + y^2 + 11 = 0, where 0 < x < y.at n=19A237132
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 870", based on the 5-celled von Neumann neighborhood.at n=39A273705
• Expansion of Product_{k>=1} ((1 + x^(4*k)) / (1 - x^k)).at n=33A285472
• Take apart the sides of each of the integer-sided scalene triangles with perimeter n (at their vertices) and rearrange them orthogonally in 3-space so that their endpoints coincide at a single point. a(n) is the total volume of all rectangular prisms enclosed in this way.at n=33A308234
• Irregular triangle read by rows where T(n,k) is the number of integer compositions of n with k weak excedances (parts on or above the diagonal), all zeros removed.at n=51A352525