23969

Appears in sequences

• Octahedral numbers: a(n) = n*(2*n^2 + 1)/3.at n=33A005900
• a(n) = (2*n - 1)*(8*n^2 - 8*n + 3)/3.at n=16A063496
• Reflected (see A074058) pentanacci numbers A074048.at n=47A074062
• G.f. (x + 1)^10/(x^10 + x^9 - x^7 - x^6 - x^5 - x^4 - x^3 + x + 1).at n=35A173243
• Semiprimes of the form (2*n^3+n)/3.at n=10A245232
• Integers n such that n+2!, n+2!+3!, n+2!+3!+4!, n+2!+3!+4!+5!, n+2!+3!+4!+5!+6!, and n+2!+3!+4!+5!+6!+7! are all prime.at n=19A267123
• Partial sums of the odd triangular numbers (A014493).at n=32A352116
• Numbers k such that A234575(k,s) = s^2 where s = A007953(k).at n=37A358034
• a(n) = smallest integer x such that Sum_{k = 2..x} 1/(k*log(log(k))) > n.at n=7A361089
• a(n) is the least integer k such that the k-th, (k+1)-th, ..., (k+n-1)-th primes are congruent to 3 mod 8.at n=4A363017