278211domain: NAppears in sequencesFibonacci-Zumkeller numbers: a(n)=n if n<=3, otherwise the smallest number >= a(n-2) + a(n-1) having at least one common factor with a(n-2), but none with a(n-1).at n=24A249357Value of p^2 + (p-1)^2/2 as p runs through A001359 (the lesser of twin primes).at n=22A372069