21323

Properties

Appears in sequences

• Number of 3 X n binary matrices up to row and column permutations.at n=14A002727
• Primes of the form k(k+1)/2+2 (i.e., two more than a triangular number).at n=39A055472
• Discriminants of imaginary quadratic fields with class number 25 (negated).at n=36A056987
• Primes of the form k^2 + 7.at n=39A079138
• If mod(n,3)=0 then a(n) = a(n-1), if mod(n,3)=1 then a(n) = Q(n-2)+Q(n-3), if mod(,n,3)=2 then a(n-3)+a(n-4)+a(n-5), where Q() = A005185().at n=50A102149
• If mod(n,3)=0 then a(n) = a(n-1), if mod(n,3)=1 then a(n) = Q(n-2)+Q(n-3), if mod(,n,3)=2 then a(n-3)+a(n-4)+a(n-5), where Q() = A005185().at n=51A102149
• Primes congruent to 24 mod 59.at n=37A142751
• Primes congruent to 34 mod 61.at n=35A142832
• Primes p such that the multiplicative order of 2 modulo p is (p-1)/7.at n=23A152307
• Primes p such that p^3 - 24 and p^3 + 24 are also primes.at n=36A153323
• a(n) = (n^3 - n + 9)/3.at n=39A155753
• a(2)=3; thereafter a(n) = smallest number m such that a(n-1)+m = (a(n-1) followed by the leading digit of m).at n=4A224754
• Primes of the form 2k^2 + k + 2.at n=18A249606
• Primes congruent to 11 mod 111.at n=34A252893
• Primes p such that the sum of the cubes of digits of p equals the sum of digits of p^3.at n=8A291052
• Prime time primes on 6-digit clocks, second definition: primes of the form HMMSS where H, MM, SS are primes, H < 24, MM and SS < 60.at n=29A295013
• Primes with record values of corresponding Fortunate numbers (A005235).at n=44A317479
• Prime numbersat n=2395