18443

Properties

Appears in sequences

• Smallest prime p==3 (mod 8) such that Q(sqrt(-p)) has class number 2n+1.at n=29A002148
• Safe primes (A005385) (p and (p-1)/2 are primes) such that 12*p+1 is also prime.at n=43A075707
• a(n) = prime(2*n*(n+1)+1).at n=32A078746
• Numbers k such that (5^k - 2^k)/3 is prime.at n=15A082182
• 4^n+3^n-2^n.at n=7A083319
• Primes congruent to 35 mod 59.at n=39A142762
• Primes congruent to 21 mod 61.at n=36A142819
• Consecutive pairs of prime point sums in A161191 (includes triples).at n=33A161192
• Primes in A168472.at n=16A168473
• Primes p such that q*p +- (p mod q) are primes, for q=8.at n=23A178416
• Number of partitions of n having no parts with multiplicity 5.at n=37A184640
• Non-palindromic balanced primes.at n=36A256076
• The Pnictogen sequence: a(n) = A018227(n)-3.at n=44A271995
• G.f. satisfies: A(x) = A(x^2) + sqrt( A(x^2) ), where A(x) = Sum_{n>=1} a(n) * x^n / 2^A274716(n).at n=18A274717
• G.f. satisfies: A(x) = A(x^2) + sqrt( A(x^2) ), where A(x) = Sum_{n>=1} a(n) * x^n / 2^A274716(n).at n=37A274717
• n such that A275391(n) = n-2.at n=55A275800
• Prime-indexed primes p such that 2*p + 1 is also a prime-indexed prime.at n=10A318294
• Primes p such that 2*p+q and 2*p+r are prime, where q and r are the next two primes after p.at n=34A340225
• a(n) is the sum of the lengths of all the segments used to draw a rectangle of height 2^(n-1) and width n divided into 2^(n-1) rectangles of unit height, in turn, divided into rectangles of unit height and lengths corresponding to the parts of the compositions of n.at n=10A340228
• a(n) = n*A340339(n)+b, where b = 1 if n is even or 2 if n is odd.at n=26A340340