699392

Appears in sequences

• a(n) = 2^(n-1)*(2^n - (-1)^n)/3.at n=11A003683
• Number of rational knots (or two-bridge knots) with n crossings (up to mirroring).at n=21A018240
• a(n) = n^2*(2*n^2 + 1)/3.at n=32A071270
• Duplicate of A018240.at n=21A090596
• a(n) = - a(n-1) + 5(a(n-2) + a(n-3)) - 2(a(n-4) + a(n-5)) - 8(a(n-6) + a(n-7)).at n=22A090597
• Starting a priori with the fraction 1/1, the denominators of fractions built according to the rule: add top and bottom to get the new bottom, add top and 9 times the bottom to get the new top.at n=9A110953
• Pentagonal numbers > 0 which are not the difference of two other pentagonal numbers > 0.at n=29A135769
• (A192466)/2.at n=10A192467
• Expansion of A(x) = Sum_{n>=0} 2^(n*(n-1)/2) * (1 + 2^(2*n+1))/3 * x^(n*(n+1)/2).at n=15A370015