44560482149
domain: N
Appears in sequences
- Pell numbers: a(0) = 0, a(1) = 1; for n > 1, a(n) = 2*a(n-1) + a(n-2).at n=29A000129
- Numbers k such that 2*k^2 - 1 is a square.at n=14A001653
- Primitive parts of Pell numbers.at n=28A008555
- Denominators of continued fraction convergents to sqrt(8).at n=28A041011
- Prime hypotenuses of Pythagorean triangles with consecutive integer sides.at n=4A056869
- Number of 2 X n binary arrays with a path of adjacent 1's from upper left corner to anywhere in right hand column.at n=26A069306
- Expansion of 1/(1 + 2*x - x^2).at n=28A077985
- a(0) = a(1) = 1; thereafter a(2*n+1) = 2*a(2*n) - a(2*n-1), a(2*n) = 4*a(2*n-1) - a(2*n-2).at n=29A079496
- Prime terms in the sequence of Pell numbers, A000129.at n=5A086383
- a(0)=0; a(1)=1; a(2n) = 4*Sum_{k=0..n} a(2k-1); a(2n+1) = a(2n) + a(2n-1).at n=29A089499
- Denominator when the numerator of the continued fraction rational approximation of sqrt(2) is prime. Also the denominators of A086395(n).at n=8A101411
- Interlaces "2*n^2 - 1 is a square" with NSW numbers.at n=28A104683
- a(2n) = A001653(n) (Numbers n such that 2*n^2 - 1 is a square), a(2n+1) = A038725(n+1).at n=28A117719
- Denominator if the numerator and denominator of the continued fraction rational approximation of sqrt(2) are both prime.at n=3A118612
- a(2n) = A100525(n), a(2n+1) = A001653(n+1); a Pellian-related sequence.at n=27A129346
- a(n) = Product_{k=1..floor((n-1)/2)} (4 + 4*cos(k*Pi/n)^2).at n=29A152118
- Prime pairs (p,q) of the form p=A002315(k), q=A001653(k) for some k.at n=5A163742
- Markov numbers that are prime.at n=29A178444
- Pell trisection: Pell(3*n+2), n >= 0.at n=9A187362
- a(n) = 2*a(n-1) + a(n-2) for n > 2, a(0) = a(1) = 1, a(2) = 2.at n=29A215928