52219

Appears in sequences

• a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n+1-k), where k = floor((n+1)/2), s = (natural numbers >= 2), t = (Lucas numbers).at n=17A024310
• a(n) = s(1)*t(n) + s(2)*t(n-1) + ... + s(k)*t(n-k+1), where k = [ n/2 ], s = (natural numbers >= 2), t = (Lucas numbers).at n=16A024873
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 21 ones.at n=30A031789
• Bond series for second parallel moment of hexagonal net.at n=15A120543
• Numbers n whose reversal is a multiple of the reversal of n+1.at n=17A250603
• a(n) = Sum_{k=0..floor(n/6)} (-1)^k * binomial(n-3*k,3*k).at n=38A348308