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%I #18 Apr 03 2023 10:36:13
%S 59,179,419,659,1019,1619,2339,3299,3539,4019,4259,5099,6299,6659,
%T 6779,8219,8819,9419,10139,10499,10859,11699,11939,12539,16139,16979,
%U 17579,18059,18539,19139,19379,21059,22619,22739,22859,24179,24419,26699,27059,27539,28619,32939,33179,34259,34499,36779,36899,37019,38459
%N Lesser of twin prime pairs of the form (40n - 21, 40n - 19).
%C This is a subsequence and the intersection of A001359 (lesser of twin primes) and A142190 (primes 19 mod 40).
%H Karl V. Keller, Jr., <a href="/A250025/b250025.txt">Table of n, a(n) for n = 1..10000</a>
%H Chris K. Caldwell, <a href="https://t5k.org/glossary/page.php?sort=TwinPrime">Twin primes</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TwinPrimes.html">Twin Primes</a>
%t Select[40Range[1000] - 21, PrimeQ[#] && PrimeQ[# + 2] &] (* _Alonso del Arte_, Nov 11 2014 *)
%t Select[Table[40n-{19,21},{n,1000}],AllTrue[#,PrimeQ]&][[All,2]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Apr 08 2019 *)
%o (Python) from sympy import isprime
%o for n in range(1,1001):
%o ..if isprime(40*n-21) and isprime(40*n-19): print(40*n-21,end=",")
%Y Cf. A142190, A001359.
%K nonn
%O 1,1
%A _Karl V. Keller, Jr._, Nov 10 2014
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