90241

Appears in sequences

• Expansion of e.g.f.: exp(arcsin(x)*exp(x)).at n=8A012316
• Structured hexagonal diamond numbers (vertex structure 5).at n=40A100178
• Numbers n with property that n^2 starts and ends with 81.at n=19A159775
• Odd composite numbers m for which A000111(m) == (-1)^( (m-1)/2 ) (mod m).at n=21A180942
• Euler pseudoprimes to base 5: composite integers such that abs(5^((n - 1)/2)) == 1 mod n.at n=36A262052
• The "residue" pseudoprimes: odd composite numbers n such that q(n)^((n-1)/2) == 1 (mod n), where base q(n) is the smallest prime quadratic residue modulo n.at n=41A307798
• 11-gonal numbers which are products of three distinct primes.at n=38A354446
• Starting from 1, successively take the smallest "Choix de Bruxelles" with factor 13 which is not already in the sequence.at n=17A360190
• Base-5 Euler-Jacobi pseudoprimes: odd composite k coprime to 5 such that 5^((k-1)/2) == (5/k) (mod n), where (5/k) is the Jacobi symbol (or Kronecker symbol).at n=27A375914
• Composite numbers k == 1, 9 (mod 10) such that 5^((k-1)/2) == 1 (mod k).at n=26A375915