19341
domain: N
Appears in sequences
- Number of 4k+3 primes (A002145) in range ]2^n,2^(n+1)].at n=18A095008
- a(n) = Sum_{k=0..n} C(floor((n+1)/2),floor((k+1)/2))*2^k.at n=11A097162
- Number triangle read by rows, related to exp(x)/(cos(x) + sin(x)).at n=29A117442
- X-toothpick sequence on Z^3 lattice (see Comments for precise definition).at n=37A160170
- Numbers k such that 3 + 10^k + 3*100^k is prime.at n=13A171149
- G.f. 1/(1-sum(n=1,N,x^(n*(3*n-1)/2))).at n=36A181324
- Odd numbers producing 4 odd numbers in the Collatz iteration.at n=30A198587
- G.f.: x * Product_{j>=1, k>=1} (1 + a(j)*x^(j*k)).at n=12A308154