20517

Appears in sequences

• Sum of next n primes.at n=18A007468
• Constant term of polynomial of degree n passing through the first n+1 consecutive prime-indexed primes.at n=14A082676
• G.f.: A(x) = F(x*F(x)^3) = F(F(x)-1) where F(x) = 1 + x*F(x)^3 is the g.f. of A001764.at n=6A153293
• Centered octahemioctahedral numbers: a(n) = (4*n^3+24*n^2+8*n+3)/3.at n=23A274974
• Numbers of the form HMMSS with primes H < 24 and MM, SS < 60, for which the number of seconds after midnight, 3600*H+60*MM+SS, is also prime.at n=9A295011
• Numbers m such that 20*m + 1, 80*m + 1, 100*m + 1, and 200*m + 1 are all primes.at n=27A372186