169975domain: NAppears in sequencesNumber of base 25 circular n-digit numbers with adjacent digits differing by 5 or less.at n=5A125388Nimsum of pairs of consecutive Lucas numbers.at n=26A165794Nim sum of distinct consecutive pairs of Lucas Numbers.at n=13A165990a(n) = Sum_{k=1..n} binomial(2*k, n-k)^2 * n/k.at n=8A198059