28982

Appears in sequences

• a(n) is the odd-length palindrome whose digits up to the center are those of n and whose center digit is equal to the digital root of the product of the factorial of n and the reverse of n.at n=27A082941
• a(1)=a(2)=1. a(n+1) = a(n) + a(smallest prime dividing n).at n=46A128216
• Number of primes between (prime(n + 1))^Pi and (prime(n))^Pi.at n=23A137380
• E.g.f.: Sum_{n>=1} tanh(n*x)^n = Sum_{n>=1} a(n)*4^(n-1)*x^n/n!.at n=5A195415
• Number of (n+2)X(n+2) 0..2 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..2 introduced in row major order.at n=1A204145
• Number of (n+2) X 4 0..2 arrays with every 3 X 3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..2 introduced in row major order.at n=1A204147
• T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every 3X3 subblock having equal diagonal elements or equal antidiagonal elements, and new values 0..2 introduced in row major order.at n=4A204153
• Palindromes that can be written in more than one way as the sum of two distinct palindromic primes.at n=20A356854
• Palindromes that can be written in more than one way as the sum of two palindromic primes.at n=23A356881
• Nonprime base-10 palindromes whose arithmetic derivative is a base-10 palindrome.at n=18A363248
• a(n) is the least positive integer that can be expressed as the sum of two distinct nonzero decimal palindromes in exactly n ways.at n=45A364836