273525

Appears in sequences

• Numbers n such that phi(n) = (phi(n+1) + phi(n-1))/2.at n=2A066167
• 1/12 the number of n X n arrays of squares of integers with every 2 X 2 subblock summing to 29.at n=11A159228
• Triangular array read by rows: row n shows the coefficients of the polynomial p(x,n) constructed as in Comments; these polynomials form a strong divisibility sequence.at n=23A327322
• Numbers k such that k*p is divisible by k+p, where p > 0 and p = A007954(k) = the product of digits of k.at n=17A334679