27948

Appears in sequences

• Numbers k such that 5*2^k - 3 is prime.at n=46A058588
• Self-convolution omits 1's at positions of triangular numbers less one.at n=29A105613
• Self-convolution of A105613.at n=22A105614
• Triangle read by rows: T(n,k) is the number of 0-1-2 trees (i.e., ordered trees with all vertices of outdegree at most two) with n edges and k pairs of adjacent vertices of outdegree 2.at n=47A126218
• The sum of the elements within a jump in a Sieve of Eratosthenes table.at n=32A179545
• First differences of A000219.at n=19A191659
• G.f.: x * Sum_{k>=1} x^k / (1 - a(k)*x^k).at n=70A309633
• a(n) = Sum_{k=0..floor(n/3)} binomial(k,3*n-9*k).at n=59A392273