33223

Properties

Appears in sequences

• Number of ordered 5-tuples of integers from [ 1,n ] with no common factors among triples.at n=23A015656
• Primes that contain digits 2 and 3 only.at n=10A020458
• Fourth term of weak prime sextet: p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1) < p(m+1)-p(m) < p(m+2)-p(m+1).at n=11A054831
• Primes such that the sum of their digits and the sum of the reciprocals of their digits is also prime.at n=19A064779
• Primes which can be represented as the sum of a prime and its reverse.at n=24A072385
• Primes p such that every decimal digit d in p appears exactly d times.at n=4A078348
• First occurrence of exactly n 1's in the binary expansion of sqrt(2).at n=12A084186
• Self-describing integers with the rule: if the digit d, part of the integer i, is odd then there are d odd digits in this integer; if the digit d is even there are d even digits.at n=15A105776
• Any digit d in the sequence says: "I am part of an integer in which you'll find d digits d".at n=19A108571
• Primes with a prime number of digits, all of them prime, that add up to a prime.at n=23A110028
• Primes in which the frequency of every digit is also prime.at n=27A113615
• a(n) is the smallest prime p such that 2^p-1 (a Mersenne number) contains 10^n or more decimal digits.at n=4A120357
• Emirps with only prime digits (i.e., 2, 3, 5, 7).at n=17A128388
• Larger of emirps (pairs) with only prime digits (A128388).at n=6A133753
• Largest prime with digit sum n and maximum digit product (or 0 if no such prime exists).at n=11A136150
• a(n) = 3*a(n-1) - 4*a(n-3), with a(0)=1, a(1)=2, a(2)=4, a(3)=9.at n=14A136298
• Emirps with a prime number of only prime digits.at n=9A137833
• Larger of emirps (pairs) with a prime number of only prime digits.at n=2A137835
• Primes made up of only 3's and a 4 and at most two 2's.at n=12A138975
• Let N(p,i) denote the result of applying "nextprime" i times to p; a(n) = smallest prime p such that N(p,2) - p = 2*n, or -1 if no such prime exists.at n=31A144103