131917

Appears in sequences

• Number of -2..2 arrays x(i) of n+1 elements i=1..n+1 with set{t,u,v in 0,1}((x[i+t]+x[j+u]+x[k+v])*(-1)^(t+u+v)) having one, three, four, five, six or eight distinct values for every i,j,k<=n.at n=9A211593
• Composite numbers k = concat(MSD(k),x) such that the sum of the aliquot parts of k is equal to the sum of the aliquot parts of x.at n=25A293479