65281

Appears in sequences

• Strong pseudoprimes to base 2.at n=10A001262
• An infinite coprime sequence defined by recursion.at n=6A002716
• Composite numbers k such that k == +-1 (mod 8) and 2^((k-1)/2) == 1 (mod k).at n=25A006971
• Cyclotomic polynomials at x=4.at n=24A019322
• Strong pseudoprimes to base 4.at n=24A020230
• Strong pseudoprimes to base 8.at n=31A020234
• Strong pseudoprimes to base 57.at n=32A020283
• Strong pseudoprimes to base 59.at n=38A020285
• Strong pseudoprimes to base 77.at n=17A020303
• Cyclotomic polynomials at x=-4.at n=24A020503
• a(n) = 4^n - 2^n + 1.at n=8A020515
• 12th cyclotomic polynomial evaluated at powers of 2.at n=4A020520
• a(n) = 2^n - n^2 + 1.at n=16A030110
• Euler-Jacobi pseudoprimes: 2^((n-1)/2) == (2 / n) mod n, where (2 / n) is a Jacobi symbol.at n=28A047713
• Super-Poulet numbers: Poulet numbers whose divisors d all satisfy d|2^d-2.at n=28A050217
• a(n) = n^4 - n^2 + 1.at n=16A060886
• a(n) = n^8 - n^4 + 1.at n=4A060893
• Zsigmondy numbers for a = 4, b = 1: Zs(n, 4, 1) is the greatest divisor of 4^n - 1^n (A024036) that is relatively prime to 4^m - 1^m for all positive integers m < n.at n=23A064080
• Numbers of the form 2^k+1 or 4^k-2^k+1.at n=23A064386
• a(n) = (lcm_{k=0..n} (2^k + 1))/(lcm_{k=0..n-1} (2^k + 1)).at n=23A066845