18023

Appears in sequences

• a(n) = [ (3rd elementary symmetric function of P(n))/(first elementary symmetric function of P(n)) ], where P(n) = {first n+2 primes}.at n=13A024453
• Numbers k such that x^k + x^3 + 1 is irreducible over GF(2).at n=40A057461
• Numbers n such that x^n + x^3 + x^2 + x + 1 is irreducible over GF(2).at n=33A057496
• Numbers n such that Fibonacci(n) is not squarefree, but for all proper divisors k of n, Fibonacci(k) is squarefree.at n=36A065069
• a(n) = ceiling(((1*n^0 + 1*n^1 + 2*n^2 + 4*n^3)/(1*n^0 + 2*n^1 + 1*n^2))^2).at n=34A085505
• a(n) = Least i in range [A165598(n),A165598(n+1)] for which abs(A165597(i)) gets the maximum value in that range.at n=32A165599
• Numbers of the form prime(n)*(prime(n)-1)/4.at n=25A171555
• Numbers n such that A229964(n) = 3.at n=20A229966
• Smallest k such that 6^n+k, 6^n+k+g, 6^n+k+2*g are consecutive primes in arithmetic progression.at n=26A233546
• Integers k such that 3*k!!! + 1 is prime where k!!! is A007661(k).at n=47A271392
• Number of prime parts in the partitions of n into 7 parts.at n=46A309436
• 1/(Integral_{x=0..1} x^(x^(x^n)) dx - 1/2), rounded to the nearest integer.at n=31A322009
• a(n) is the least number k such that A066323(k) = n.at n=23A342728
• Number of solid partitions of n with 7 parts.at n=10A389774