521300

Appears in sequences

• a(n) = Sum_{k=1..n} Sum_{j=1..k} (prime(k) - prime(j))^2.at n=24A062022
• For every positive integer m, let u(m) = (d(1),d(2),...,d(k)) be the unitary divisors of m. The sequence (a(n)) consists of integers of the form d(k)/d(1) + d(k-1)/d(2) + ... + d(k)/d(1).at n=30A229999
• Numbers k whose reversal divides the reversal of k+1.at n=32A250602
• a(n) = the fractional part of 1 / A003592(n) read backwards.at n=21A299025