22717

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 51.at n=36A020390
• Numbers k such that 30*R_k + 1 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=24A055520
• Primes p of Erdos-Selfridge class 4+ with largest prime factor of p+1 not of class 3+.at n=17A129472
• Prime numbers p for which the quintic polynomial x^5 - x - 1 modulo p completely factors into linear polynomials.at n=16A135844
• Prime numbers p not of the form 10*k+1 for which the quintic polynomial x^5-x-1 modulus p is factorizable into five binomials.at n=12A135845
• Partial sums of A053872.at n=14A155974
• Lesser of two Pythagorean primes for which the Pythagorean triangles have the same area.at n=14A157184
• Primes of the form 3n^2 + 10.at n=14A201480
• a(n) = 1 + n + ((n-1)*n^2)/2.at n=36A218152
• Triangle, read by rows, where T(n,k) is defined for n>=1, k=1..2*n-1, by a formula analogous to the second-order Eulerian triangle A008517.at n=56A219120
• Central terms in rows of triangle A219120.at n=7A219121
• Primes whose base-3 representation also is the base-2 representation of a prime.at n=39A235265
• G.f.: (1-x + sqrt(1 - 14*x + x^2)) / (2*(1 - 14*x + x^2)).at n=4A245923
• Expansion of (1/(1 - x))*Sum_{k>=0} k!*x^(k*(k+1)/2)/Product_{j=1..k} (1 - x^j).at n=24A303664
• Number of nX2 0..1 arrays with every element unequal to 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=7A304421
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=37A304427
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4 or 5 king-move adjacent elements, with upper left element zero.at n=43A304427
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.at n=37A305692
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4, 5 or 6 king-move adjacent elements, with upper left element zero.at n=43A305692
• T(n,k)=Number of nXk 0..1 arrays with every element unequal to 1, 2, 3, 4, 5 or 7 king-move adjacent elements, with upper left element zero.at n=37A305961