43960

Appears in sequences

• a(1) = 2; a(n+1) = a(n)-th composite.at n=45A022450
• Denominators of continued fraction convergents to sqrt(786).at n=3A042515
• a(n) = a(1) + a(2) + ... + a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2, and a(3) = 3.at n=15A049956
• a(0) = 1, a(n) = 20*sigma[3](n).at n=13A091983
• a(n) = 4*n*(4*n^2 + 1).at n=14A144965
• Numbers n such that n^32+1 and (n+2)^32+1 are both prime.at n=16A217992
• Numbers k such that (26*10^k + 49)/3 is prime.at n=24A282536
• Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 3 king-move adjacent elements, with upper left element zero.at n=13A303726
• a(n) = 36*n^2 - 4*n (n>=1).at n=34A304380
• Nonunitary weird numbers: numbers that are nonunitary abundant but not nonunitary pseudoperfect.at n=10A327948
• Number of labeled histories for rooted ternary trees with 2n+1 leaves if simultaneous trifurcations are allowed.at n=4A381486