31973

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 20.at n=6A031608
• a(1) = 9; a(2n) = smallest prime that is a right concatenation of a(2n-1) and a number with no insignificant zeros and a(2n+1) = smallest prime ending in ( the least significant digits) a(2n). Alternate left and right concatenation yielding primes.at n=4A069621
• a(1) = 9; a(2n) = smallest prime starting (most significant digits) with a(2n-1). a(2n+1) = smallest prime ending (least significant digits)in a(2n).at n=4A069636
• Primes of the form 6n^2 - 1.at n=29A090686
• Primes p such that p's set of distinct digits is {1,3,7,9}.at n=22A108386
• Home primes whose homeliness is greater than 4.at n=22A133963
• Home primes whose homeliness is 5.at n=14A133964
• Primes p such that continued fraction of (1 + sqrt(p))/2 has period 7: primes in A146332.at n=39A146352
• Primes p such that (p-1)*p*(p+1)-p-2 and (p-1)*p*(p+1)+p+2 are primes.at n=32A154942
• Coefficients in the expansion of C^3/B^4, in Watson's notation of page 106.at n=12A160463
• Prime numbersat n=3430