68697

Appears in sequences

• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers), t = (primes).at n=25A024478
• Duplicate of A024478.at n=25A025090
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (Lucas numbers), t = (primes).at n=24A025098
• Natural numbers written out with their digits grouped in sets of 5 (leading zeros omitted).at n=25A091341
• Numbers for which iteration of the powertrain map of A133500 takes a record number of steps to converge.at n=7A133503
• Number of 2-Abelian equivalence classes of words of length n over an alphabet of size 3.at n=17A289658
• Numbers k such that k | (sigma(k-2) + sigma(k-1) + sigma(k+1) + sigma(k+2)).at n=10A296027