2977920

Appears in sequences

• Numbers n such that sigma(n) is congruent to n mod phi(n).at n=29A066679
• Smallest solution to x+n*phi(x) = sigma(x) = x+n*A000010(x) = A000203(x).at n=11A076374
• Triangle read by rows: expansion of p(t) = (1 + t)^x/(1 + (1 + t)^n) with weight factor 2^(n+1)*n!.at n=21A137369
• Triangle read by rows: T(n,k) is the number of linear chord diagrams on 2n vertices with one marked chord such that exactly k of the remaining n-1 chords are excluded by (i.e., are outside and do not contain) the marked chord.at n=30A336601