62700

Appears in sequences

• Numbers k such that prime(2*k) - prime(k) == 0 (mod k).at n=18A066894
• a(n) = n*(n-1)*(n^2 + 2)/6.at n=25A071244
• Larger member of an infinitary amicable pair.at n=13A126170
• Infinitary amicable numbers.at n=26A127664
• a(1)=11. For n>1, a(n) is LCM of a(n-1) and largest integer <= sqrt(a(n-1)).at n=5A179204
• The number of ways to color the vertices of all (11) simple unlabeled graphs on 4 nodes using at most n colors.at n=11A199394
• a(n) = number of knight's move paths of minimal length n steps, from origin (0,0) at center of an infinite open chessboard to square (0,0) for n=0; square (2,-1) for n=1; and square (2n-3, (n+1)mod 2) for n>=2.at n=11A242511
• a(n) = maximal number of shortest knight's move paths, from origin at center of an infinite open chessboard, to any square within n moves.at n=11A242513
• Number of preferential arrangements of n labeled elements such that the minimal number of elements per rank equals 3.at n=8A245856
• Number of (n+2) X (3+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00010101 or 01010101.at n=10A259737
• a(n) = 4*n*(n^2 + 2).at n=24A292022
• Larger of bi-unitary amicable pair.at n=16A292981
• Larger of tri-unitary amicable numbers pair: numbers (m, n) such that tsigma(m) = tsigma(n) = m + n, where tsigma(n) is the sum of the tri-unitary divisors of n (A324706).at n=10A324709
• a(n) = ((n + 1)^2 * (5*n + 4)*n) / 12.at n=19A368046