21157

Properties

Appears in sequences

• Primes that are palindromic in base 2 (but written here in base 10).at n=36A016041
• Numbers whose base-2 representation has exactly 13 runs.at n=29A043580
• Primes p such that the decimal digits of p^2 can be partitioned into two or more nonzero squares.at n=38A048646
• Numbers k such that (29*10^(k-1) + 7)/9 is a depression prime.at n=5A082705
• Primes produced by repeated application of the formula p -> (6p +- 5) starting at the prime 2.at n=24A086321
• a(n) = prime(Pell(n)).at n=9A088747
• Primes congruent to 51 mod 61.at n=39A142849
• a(n) is the number whose binary expansion is A153498(n).at n=7A153497
• Take A163498(n) written in binary, insert a 0 before every 1. a(n) is the decimal equivalent of the result.at n=27A163499
• Primes of the form 10n^2 - 3.at n=11A201962
• Consider two consecutive primes {p,q} such that P=2p+q and Q=2q+p are both prime. The sequence gives primes Q.at n=42A248483
• Primes p such that 2*p + 1 is abundant.at n=25A267476
• Primes dividing nonzero terms in A002065.at n=27A328704
• Primes which, when added to their reversals, produce palindromic primes.at n=15A342681
• Expansion of g.f. A(x) satisfying A(x) = A( x^2*(1+x)^2 ) / x.at n=14A369552
• Prime numbers whose base-2 representation is a "nested" palindrome.at n=10A373581
• Numbers whose base-2 representation is a "nested" palindrome.at n=47A373941
• Prime numbersat n=2378