20955

Appears in sequences

• 1 + Sum_{n>=1} a_n x^n = Product_{n>=1} (1-x^n)^prime(n).at n=29A007441
• Triangle T(n,k) of number of minimal 2-covers of a labeled n-set that cover k points of that set uniquely (k=2,..,n).at n=51A057963
• Number of incongruent ways to tile a 5 X 2n room with 1x2 Tatami mats. At most 3 Tatami mats may meet at a point.at n=40A068930
• a(n) = 676*n - 1.at n=30A158393
• Number of indecomposable (by shuffling) alternating n-anagrams.at n=6A218827
• Triangle read by rows: T(n,k) (n >= 1, 1 <= k <= n) = number of alternating anagrams on n letters (of length 2n) which are decomposable into at most k components.at n=21A239895
• Number of length n+3 0..3 arrays with at most one downstep in every 3 consecutive neighbor pairs.at n=4A258725
• T(n,k)=Number of length n+k 0..3 arrays with at most one downstep in every k consecutive neighbor pairs.at n=25A258730
• Number of length n+5 0..3 arrays with at most one downstep in every n consecutive neighbor pairs.at n=2A258735
• Molien series for invariants of finite Coxeter group A_8.at n=66A266777
• Numbers k such that 8*10^k - 51 is prime.at n=21A290330
• Smallest integer k >= 0 such that the maximum digit of k^2 written in factorial base equals n.at n=11A301872
• a(n) = 2*(a(n-1) + a(n-3)) - a(n-4), with a(0) = 1, a(1) = 2, a(2) = 5 and a(3) = 12.at n=12A319172
• Number of ways an n-set can be written as the union of 2 sets each with 4 or more elements and whose intersection contains exactly 3 elements.at n=6A349415
• a(n) is the smallest error in trying to solve n^5 = x^5 + y^5: for each n from 2 on, find positive integers x and y, x <= y < n such that |n^5 - x^5 - y^5| is minimal and let a(n) = n^5 - x^5 - y^5. In case of a tie, choose the solution with smallest y.at n=20A369855