33780

Appears in sequences

• Number of step cyclic shifted sequence structures using exactly two different symbols.at n=24A056434
• Numbers k such that 2*k-1, 4*k-1, 6*k-1 and 8*k-1 are primes.at n=21A124487
• Triangle of polynomial coefficients of the polynomial factors defined in A074051.at n=56A197184
• Number of composites removed in each step of the Sieve of Eratosthenes for 10^7.at n=13A227155
• Number of nX3 0..1 arrays with every element equal to 0, 2 or 3 horizontally or vertically adjacent elements, with upper left element zero.at n=13A301603
• a(n) = Sum_{k=0..n} (k+1) * 2^k * binomial(2*n+1,n-k).at n=6A386955