19075

Appears in sequences

• a(n) = floor((7*2^(n+1)-9*n-10)/3).at n=12A005262
• Fibonacci sequence beginning 7, 15.at n=16A022389
• a(1) = 2; a(n+1) = a(n)-th nonprime, where nonprimes begin at 1.at n=39A025003
• Number of bipartite graphs with 4 edges on nodes {1..n}.at n=8A053527
• a(n) = 4^n mod n^4.at n=12A066608
• Smallest integer > 1 which is both n-gonal and centered n-gonal.at n=31A072277
• Numbers n with the property that n is an anagram of the digits of the distinct prime factors of n.at n=4A096595
• Triangle read by rows: T(n,k) is number of labeled bipartite graphs with n nodes and k edges.at n=46A117279
• Numbers k such that 6*p(k)*p(k+1)*p(k+2)*p(k+3)*p(k+4)*p(k+5)-1 and 6*p(k)*p(k+1)*p(k+2)*p(k+3)*p(k+4)*p(k+5)+1 are twin primes with p(h) = h-th prime.at n=26A129311
• a(n) = 66*n^2 + 1.at n=17A158689
• a(n) = n*(n^2 - 4*n + 5)/2.at n=35A162607
• Number of n X 4 binary arrays with all 1s connected, all corners 1, and no 1 having more than two 1s adjacent.at n=10A163735
• Sequence defined by the recurrence formula a(n+1)=sum(a(p)*a(n-p)+k,p=0..n)+l for n>=1, with here a(0)=1, a(1)=5, k=0 and l=-2.at n=7A176757
• 34-gonal numbers: a(n) = n*(32*n-30)/2.at n=35A282854
• Partial sums of A299268.at n=22A299269
• Composite numbers that are anagrams of the concatenation of their prime factors.at n=9A306474
• Numbers k such that the second k binary digits of Pi represent a prime (leading zeros allowed).at n=11A333649
• G.f. A(x) satisfies A(x) = 1/(1 - x)^3 + x*(1 - x)^3*A(x)^3.at n=6A366034