19207

Properties

Appears in sequences

• Generalized Catalan Numbers x^2*A(x)^2 -(1-x+x^2+x^3+x^4+x^5)*A(x) + 1 =0.at n=19A023422
• Number of partitions satisfying cn(0,5) < cn(1,5) + cn(4,5).at n=36A039842
• Numbers whose base-7 representation contains exactly four 6's.at n=30A043420
• Primes at which the difference pattern X42Y (X and Y >= 6) occurs in A001223.at n=36A052164
• Least prime in A023200 (lesser of 4-twins) such that the distance to the next 4-twin is 6*n.at n=29A052351
• Smallest prime p such that n is a solution mod p of x^4 = 2, or 0 if no such prime exists.at n=12A065902
• Primes of the form 2^r*7^s - 1.at n=12A077314
• Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <=6 (i.e., when d=2,4 or 6) and forming d-pattern=[4,2,6]; short d-string notation of pattern = [426].at n=10A078850
• Primes of the form 8*k^2 - 1.at n=22A090684
• Primes p such that p^2-p-1 and p^2-p+1 are twin primes.at n=37A120364
• Primes p such that p - q = 24, where q is the previous prime before p; or prime numbers preceded by precisely 23 composite numbers.at n=32A126720
• Primes congruent to 32 mod 59.at n=35A142759
• Primes congruent to 53 mod 61.at n=37A142851
• Primes of the form 2*p^2 + 4*p + 1, where p is also prime.at n=10A164041
• Primes p that p//13 and p//31 are consecutive primes.at n=28A176601
• a(0)=0, a(1)=1, a(n) = a(n-1) + (a(n-2) XOR n).at n=20A182537
• The Riemann primes of the psi type and index 1.at n=33A197185
• Primes remaining primes under map 2<=>9 (interchange of decimal digits 2 and 9).at n=34A198146
• a(n) = 8*7^n-1.at n=4A198689
• Primes of the form 7n^3-1.at n=2A200915