39195

Appears in sequences

• a(n) is the concatenation of n and 5n.at n=38A019553
• Triangle read by rows: T(n,k) is the number of set partitions of the set {1,2,...,n} containing k blocks of size 2 (0 <= k <= floor(n/2)).at n=31A124498
• a(n) = 81*n^2 - 9.at n=21A157909
• a(n) = [x^n] Product_{k=1..n} (1 + x^k)^(n-k+1).at n=9A206229
• Number of integer-sided pentagons having perimeter n, modulo rotations but not reflections.at n=48A293822
• Numbers n such that there are precisely 11 groups of orders n and n + 1.at n=3A295994
• The odd edge of a primitive 3-simplex (0, b=A031173, c=A031174, d=A031175).at n=43A298047
• Number of nX3 0..1 arrays with every element unequal to 0, 1 or 3 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=19A317768