27773

Properties

Appears in sequences

• a(n) = a(n-1)+a(m), where m=2n-2-2^(p+1) and 2^p<n-1<=2^(p+1), for n >= 4.at n=31A050071
• Primes with either no internal digits or all internal digits are 7.at n=46A069682
• a(n) = A085956(3n+1).at n=35A086362
• Primes such that the outer 2 digits are k and k+1 and all inner digits are 7, where 0 < k < 9.at n=2A108824
• Primes arising as the 10's complement of A109862(n).at n=22A109863
• Primes p of the form A152539(n) + 1.at n=35A152540
• Primes of the form 10*k^2+14*k+5, k >= 0.at n=25A154412
• Primes containing 777 as a substring.at n=6A167282
• Smallest m such that n = sum of digits of A108971(m).at n=36A179988
• Primes of the form 3*n^3-10.at n=3A200909
• Primes of the form 7n^2 - 10.at n=2A201855
• Primes that contain only the digits (2, 3, 7).at n=40A214704
• Number of numbers which require n iterations of the unitary totient function (A047994) to reach 1.at n=19A225173
• Sophie Germain primes p such that p+6 and p-6 are primes.at n=26A278869
• The difference between 10^n and the lesser of the twin primes immediately before.at n=41A327133
• Prime numbersat n=3031