19345

Appears in sequences

• Pseudoprimes to base 3.at n=33A005935
• Pseudoprimes to base 7.at n=27A005938
• a(0) = 1, a(n) = 23*n^2 + 2 for n>0.at n=29A010013
• Pseudoprimes to base 17.at n=38A020145
• Pseudoprimes to base 21.at n=34A020149
• Pseudoprimes to base 63.at n=36A020191
• Pseudoprimes to base 66.at n=38A020194
• Pseudoprimes to base 72.at n=41A020200
• Strong pseudoprimes to base 3.at n=10A020229
• Strong pseudoprimes to base 9.at n=23A020235
• Strong pseudoprimes to base 27.at n=22A020253
• Strong pseudoprimes to base 81.at n=33A020307
• Numbers k such that the continued fraction for sqrt(k) has period 51.at n=32A020390
• Numerator of Sum_{k=0..n} 1/binomial(n,k).at n=16A046825
• Numerator of (1/n)*Sum_{k=0..n-1} 1/binomial(n-1,k) for n>0 else 0.at n=17A046878
• Base-3 Euler-Jacobi pseudoprimes.at n=15A048950
• a(n) = n*(n^2 + 1) if n is even, otherwise (n - 1/2)*(n^2 + 1).at n=27A071289
• Pseudoprimes to bases 3 and 7.at n=5A083735
• Position of n! among the lexicographically ordered permutations of digits of n!.at n=13A116983
• Nonprimes k such that 3^k == 3 (mod k).at n=41A122780