a(1) = 2. For n>1, a(n) = smallest m such that m == 0 (mod prime(n)), m + 1 == 0 (mod prime(n+1)) and m-1 == 0 (mod prime(n-1)).

A078455

a(1) = 2. For n>1, a(n) = smallest m such that m == 0 (mod prime(n)), m + 1 == 0 (mod prime(n+1)) and m-1 == 0 (mod prime(n-1)).