28682

Appears in sequences

• a(n) = F(n+3) + c(n) where F(k) is k-th Fibonacci number and c(n) is n-th number that is 1 or 2 or is not a Fibonacci number.at n=19A022809
• a(n) = b(n) + d(n), where b(n) = (n-th Fibonacci number > 2) and d(n) = (n-th number that is 1 or is not a Lucas number).at n=19A023496
• a(n) = b(n) + d(n), where b(n) = (n-th Fibonacci number > 1) and d(n) = (n-th number that is 1, 2, or 3, or is not a Lucas number).at n=20A023500
• Palindromic even lucky numbers.at n=40A045960
• Palindromes with exactly 2 palindromic prime factors (counted with multiplicity), and no other prime factors.at n=33A046376
• Palindromes with exactly 2 distinct palindromic prime factors.at n=29A046408
• Palindromic even squarefree numbers with an even number of distinct prime factors.at n=31A075811
• Palindromic even numbers with exactly 2 prime factors (counted with multiplicity). Equivalently, palindromic numbers of the form 2*p with p prime.at n=21A075813
• "Ceiling of hypotenuses": a(n) = ceiling(sqrt(a(n-1)^2 + a(n-2)^2)), a(1)=1, a(2)=3.at n=38A104805
• Third entry in row n of triangle in A169945.at n=23A169947
• Palindromic Ulam numbers.at n=42A173542
• Number of (w,x,y,z) with all terms in {0,...,n} and |w-x|<|x-y|<|y-z|.at n=20A212902
• Number of parts in all proper twice partitions of n.at n=9A328042
• Palindromes that can be written in more than one way as the sum of two palindromic primes.at n=20A356881