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%I #28 May 02 2021 21:42:28
%S 3,13,103,1009,10099,100189,1000033,10000453,100000123,1000000093,
%T 10000000597,100000000069,1000000000189,10000000000279,
%U 100000000001173,1000000000000399,10000000000001719,100000000000002733,1000000000000002493,10000000000000000087
%N Lesser of the first cousin prime pair with n digits.
%C Sum of reciprocals converges towards 0.421066...
%C It is only a (plausible) conjecture that this sequence is well-defined. See A152052. - _N. J. A. Sloane_, Aug 22 2014
%H Abhiram R Devesh, <a href="/A240167/b240167.txt">Table of n, a(n) for n = 1..100</a>
%F For n > 1, a(n) = 10^(n-1) + A227432(n-1), assuming a(n) exists. - _Jens Kruse Andersen_, Aug 22 2014
%o (Python)
%o import sympy
%o for i in range(100):
%o a=(10**i)
%o p=sympy.nextprime(a)
%o while not sympy.isprime(p+4):
%o p=sympy.nextprime(p)
%o print(p)
%o (PARI)
%o a(n)=my(p=nextprime(10^(n-1))); while(!isprime(p+4), p=nextprime(p+1)); return(p)
%o vector(50, n, a(n)) \\ _Derek Orr_, Aug 04 2014
%Y Cf. A023200, A152052, A227432, A240170.
%K nonn,base
%O 1,1
%A _Abhiram R Devesh_, Aug 02 2014
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