20602

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 97.at n=10A020436
• Base-10 palindromes that start with 2.at n=28A043037
• Composite palindromes whose sum of prime factors is prime (counted with multiplicity).at n=44A046365
• Palindromes with exactly 2 palindromic prime factors (counted with multiplicity), and no other prime factors.at n=28A046376
• Palindromes with exactly 2 distinct palindromic prime factors.at n=24A046408
• Numbers k such that k^2 contains only digits {0,2,4}, not ending with zero.at n=3A058423
• Palindromic even squarefree numbers with an even number of distinct prime factors.at n=16A075811
• Palindromic even numbers with exactly 2 prime factors (counted with multiplicity). Equivalently, palindromic numbers of the form 2*p with p prime.at n=12A075813
• Consider all (2n+1)-digit palindromic primes of the form 30...0M0...03 (so that M is a palindrome with <= 2n-1 digits); a(n) = smallest such M.at n=47A100955
• Consider all (2n+1)-digit palindromic primes of the form 90...0M0...09 (so that M is a palindrome with <= 2n-1 digits); a(n) = smallest such M.at n=41A100957
• a(n) = (1/sqrt(26))((5+sqrt(26))^(n+1)-(5-sqrt(26))^(n+1)).at n=4A109107
• Numbers k such that k and k^2 use only the digits 0, 2, 3, 4 and 6.at n=20A136883
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 5 and 6.at n=49A136898
• Numbers k such that k and k^2 use only the digits 0, 2, 4 and 6.at n=6A136902
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 7.at n=13A136903
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 8.at n=32A136904
• Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 9.at n=18A136905
• Half the number of nX4 binary arrays with each element equal to at least two neighbors.at n=10A180753
• Dates after Jan 01 00 in chronological order which are palindromic when they are written in the format D.M.YY. The terms are listed as numbers (without the dots).at n=15A210890
• Dates after Jan 01 00 in chronological order which are palindromic when they are written in the format D.M.YY. The terms are listed as numbers. Leading zeros of the terms are suppressed.at n=15A210892