24151

Properties

Appears in sequences

• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 100 ones.at n=17A031868
• Concatenation of prime p and nextprime(p) is prime -> cycles of 2 steps possible.at n=8A036339
• The sequence e when b=[ 1,0,1,1,1,... ].at n=43A042953
• Numbers p from A001125 such that 2*p-3 is prime.at n=31A063939
• Numbers k such that binomial(2k,k)+1 is prime.at n=40A066699
• Primes of the form 5k^2 + 5k + 1.at n=35A090562
• Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5...at n=25A098039
• Primes from merging of 5 successive digits in decimal expansion of Zeta(2) or (Pi^2)/6.at n=1A105378
• Primes p such that p+1, p+2 and p+3 have equal number of divisors.at n=28A119711
• Primes p for which Sum_{1 <= n < p} (n!|p) == 0 (mod p), where (n!|p) is the Legendre symbol.at n=37A131652
• Mother primes of order 11.at n=31A136070
• Lesser of two consecutive primes, p < q, such that both p*q+p-q and p*q-p+q are prime numbers.at n=29A154553
• Primes p of the form 4m+3 for which there are exactly as many primitive roots modulo p in the interval [0,p/2] as in the interval [p/2,p].at n=25A172490
• Primes p such that reversal(p) - 13 is a square.at n=25A176371
• Number of 6X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 6 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).at n=19A192706
• Primes p such that floor(log(p)) + p^2 is prime.at n=34A225626
• Odd integers k such that for every m >= 1 the numbers k*4^m - 1 have at least three prime factors, not necessarily distinct, and k*4^m - 1 has at least two-element covering set.at n=36A233552
• Number of partitions p of n not including round(mean(p)) as a part. (This is "Mathematica round"; for round(x) defined as floor(x + 1/2), see A241734.)at n=42A241339
• a(n) = floor(5*prime(n)^2 / 4).at n=33A246010
• Number of length n+3 0..6 arrays with every four consecutive terms having the sum of some three elements equal to three times the fourth.at n=15A248535