99585

Appears in sequences

• a(n) = least natural number k such that the distance between (n, sigma(n)) and (n+k, sigma(n+k)) is an integer (i.e., k^2 + (sigma(n+k) - sigma(n))^2 is a square), if such k exists; 0 otherwise.at n=2A066790
• Number of partitions of an n-set without blocks of size 2.at n=11A097514
• 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=36A124498
• a(0)=a(1)=1. For n >= 2, a(n) = a(n-2) + a(n-1) + (number of terms from among {a(0),a(1),a(2),...a(n-1)} which are <= n).at n=22A128610
• Residues of the Lucas - Lehmer primality test for M(17) = 131071.at n=12A129222
• Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,3,2,1,4 for x=0,1,2,3,4.at n=10A196075
• Odd bisection of A097514.at n=5A364446