87685

Appears in sequences

• Odd integers m such that phi(m) | sigma(m).at n=27A015715
• Numbers n such that sigma(n) = 2*phi(n).at n=8A062699
• Numbers k such that sigma(k) = phi(k*bigomega(k)).at n=28A068400
• Numbers n such that sigma(n) = phi(3n).at n=14A074891
• Numbers k such that k, 2*k and 4*k are balanced numbers (A020492).at n=21A076376
• Number of monotonic matrices of order n.at n=3A086976
• Balanced numbers (A020492) k such that k mod 12 = 1.at n=5A110597
• Difference between sum of largest parts and sum of smallest parts of all partitions of n into an even number of parts.at n=36A211881
• Number of cyclotomic cosets of 7 mod 10^n.at n=34A220019
• Numbers k such that gcd(sigma(k), phi(k)) (A009223) attains record values.at n=31A222711
• Number of (n+1)X(1+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=6A236782
• Number of (n+1)X(7+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=0A236788
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=21A236789
• T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median plus the lower median minus the minimum of every 2X2 subblock equal.at n=27A236789
• Sum of the three largest parts in the partitions of 4n into 4 parts.at n=14A243011
• Numbers n such that psi(n) = 2*phi(n).at n=36A292390
• a(0) = 1 by convention; for n>0, a(n) is the number of points in the n-th figure shown in A255011 (meaning the figure with 4n points on the perimeter).at n=11A331449