1525870529

Appears in sequences

• a(n) = 4*a(n-1) - a(n-2) with a(0) = 0, a(1) = 1.at n=17A001353
• a(n) = 4*a(n-2) - a(n-4) for n > 1, a(n) = n for n = 0, 1.at n=34A002530
• Pisot sequence E(4,15): a(n) = floor(a(n-1)^2/a(n-2)+1/2) for n>1, a(0)=4, a(1)=15.at n=15A010905
• Bisection of A001353. Indices of square numbers which are also octagonal.at n=8A028230
• a(2*n) = A028230(n), a(2*n+1) = -A067900(n+1).at n=16A110294
• a(n) = -14*a(n-1) - a(n-2), with a(1) = a(2) = 1.at n=9A122572
• a(0) = 1, a(1) = -4, a(n) = -4*a(n-1) - a(n-2) for n > 1.at n=16A125905
• Expansion of x *(1+x) *(x^2+1) *(15*x^4+1) / ( (x^4-2*x^3+2*x^2+2*x+1) *(x^4+2*x^3+2*x^2-2*x+1) ).at n=36A140806
• Expansion of x *(1+x) *(x^2+1) *(15*x^4+1) / ( (x^4-2*x^3+2*x^2+2*x+1) *(x^4+2*x^3+2*x^2-2*x+1) ).at n=37A140806
• Expansion of x *(1+x) *(x^2+1) *(15*x^4+1) / ( (x^4-2*x^3+2*x^2+2*x+1) *(x^4+2*x^3+2*x^2-2*x+1) ).at n=38A140806
• Denominators of continued fraction convergents to sqrt(3)/2.at n=17A144536
• Numerators b(n) of Pythagorean approximations b(n)/a(n) to sqrt(3).at n=15A195503
• Denominators of the other-side convergents to sqrt(3).at n=32A259592
• Denominator of Kirchhoff index of ladder graph L_n.at n=16A265031
• a(n) = numerator(r(n)) where r(n) = (((1/2)*(sqrt(3) + 1))^n - ((1/2)*(sqrt(3) - 1))^n * cos(Pi*n))/sqrt(3).at n=34A305491
• Primitive part of A001353(n).at n=16A306825
• a(n) is the greatest divisor of A001353(n) that is coprime to A001353(m) for all positive integers m < n.at n=16A309526