18814

Appears in sequences

• If p(k) is the k-th prime, then the n-th set of 3 consecutive cousin prime pairs starts at p(a(n)).at n=25A095970
• If p(k) is the k-th prime, then the n-th set of 4 consecutive cousin prime pairs starts at p(a(n)).at n=5A095971
• Start with a(1)=1; for n >= 1, a(n+1)=a(n)+a(k) with k=[n-n-th digit of "e"]. If k<0 or k=0, then a(k)=0.at n=36A133392
• Even composites in A145832 with at least three distinct prime factors.at n=7A145916
• a(n) = 2*prime(n)^2 - 4.at n=24A153480
• Positions of records in A166133.at n=34A256404
• Numbers n such that A166133(n) sets a new record and also satisfies A166133(n)=A166133(n-1)^2-1.at n=19A256422
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 542", based on the 5-celled von Neumann neighborhood.at n=37A272811
• Numbers k for which rank of the elliptic curve y^2=x^3+k*x is 4.at n=16A309031
• Number of permutations p of [n] such that for each i in [n] we have: (i>1) and |p(i)-p(i-1)| = 1 or (i<n) and |p(i)-p(i+1)| = 1.at n=11A363181