247105

Appears in sequences

• a(n) = n^4/2 - n^3 + 3*n^2/2 - n + 1 = (n^2 + 1)*(n^2 - 2*n + 2)/2.at n=27A058919
• Numbers n such that the number of primes between n^2 and (n+1)^2 = the number of primes between n and Reverse(n) (inclusive).at n=33A074817
• Numerator of Hermite(n, 1/24).at n=4A159949
• Composite numbers n with the property that phi(n) divides (n-1)^2.at n=25A173703
• Composite numbers k such that phi(k) divides d*(k - 1) for some squarefree divisor d of k - 1.at n=2A337316