34454
domain: N
Appears in sequences
- Triangle read by rows: T(n,k) is the number of deco polyominoes of height n and such that the sum of the bottom levels of all columns is k (n>=1, k>=0; informally, the number of the "missing" cells in the right bottom corner of the polyomino). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=46A122104
- Row sums of A136375.at n=11A151711
- Smallest natural number requiring n letters in Spanish.at n=43A161353
- a(n) = name of smallest positive number in Spanish which has the letter E in the n-th position starting from the end, or -1 if no such number exists.at n=43A173182
- A symmetrical sum triangle sequence:a(n)=vector(a(n-1)).Reverse(vector(a(n-1));a(0)=1;a(1)=2;t(n,m)=2+a(n)-a(m)-a(n-m).at n=48A176698
- A symmetrical sum triangle sequence:a(n)=vector(a(n-1)).Reverse(vector(a(n-1));a(0)=1;a(1)=2;t(n,m)=2+a(n)-a(m)-a(n-m).at n=51A176698
- Smallest k such that k*2*p(n)^2+1=q is prime, k*2*q^2+1=r, k*2*r^2+1=s, k*2*r^2+1=t, r, s, and t are also prime.at n=5A224496