191861

Properties

Appears in sequences

• a(0) = 1, a(1) = 5, a(n) = 4*a(n-1) - a(n-2).at n=9A001834
• a(2*n) = a(2*n-1) + a(2*n-2), a(2*n+1) = 2*a(2*n) + a(2*n-1); a(0) = a(1) = 1.at n=19A002531
• Limit of the sequence obtained from S(0) = (1,1) and, for n > 0, S(n) = I(S(n-1)), where I consists of inserting, for i = 1, 2, 3..., the term a(i) + a(i+1) between any two terms for which 7*a(i+1) <= 11*a(i).at n=18A082630
• Numerators of the rational convergents to sqrt(3) if both numerators and denominators are primes.at n=4A086386
• Prime numerators of the rational convergents to sqrt(3).at n=7A096146
• Expansion of (1 + x + x^2)/(1 - 4x^2 + x^4).at n=18A108412
• Number of Khalimsky-continuous functions with a three-point codomain.at n=17A131887
• Numerators of principal and intermediate convergents to 3^(1/2).at n=27A143642
• Numerators of the lower principal convergents and the lower intermediate convergents to 3^(1/2).at n=18A143643
• Numerators of fractions x^n + y^n, where x + y = 1 and x^2 + y^2 = 2.at n=18A173299
• Primes in A173299.at n=10A173929
• Primes of the form k^2 + 17.at n=23A228244
• a(n) = a(n-1) + (if a(n-1) is odd a(n-2) else a(n-3)) with a(0) = 0, a(1) = 1.at n=29A254308
• Probable primes in sequence {s_k(4)}, where s_k(4) = 4*s_{k-1}(4) - s_{k-2}(4), k >= 2, s_0(4) = 1, s_1(4) = 5.at n=4A299107
• a(n) = MPR2(n, 4), where MPR2(n, x) is the (monic) minimal polynomial of 2*cos(2*Pi/n) as defined in A232624.at n=18A309040
• Primes of the form p+q*(r+s), where p,q,r,s are consecutive primes.at n=16A343449
• Prime numbersat n=17318