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A282407 Semiprimes p such that next semiprime after p is p + 40. 2

%I #10 May 23 2021 02:55:32

%S 741841,1633213,1889467,1946677,2210557,2440203,2655427,2660857,

%T 2729091,2749273,2774911,3077323,3724909,3977473,4021507,4030891,

%U 4323301,4372337,4408581,4421713,4608574,4640419,4836223,5640861,5691531,6148599,6166101,6429853,6786523

%N Semiprimes p such that next semiprime after p is p + 40.

%C Note that a(1) = 741841 = A131109(40).

%C Smallest difference between two consecutive terms occurs first at a(22060) = 1141901643 because a(22061) = 1141901683 = 1141901643 + 40.

%H Zak Seidov, <a href="/A282407/b282407.txt">Table of n, a(n) for n = 1..23671</a>

%o (PARI) is(p) = if(bigomega(p)==2 && bigomega(p+40)==2, for(i=p+1, p+39, if(bigomega(i)==2, return(0))); 1); \\ _Jinyuan Wang_, May 23 2021

%Y Cf. A001358, A131109, A217030, A217335, A217357.

%K nonn

%O 1,1

%A _Zak Seidov_, Feb 14 2017

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Last modified May 5 01:44 EDT 2024. Contains 372257 sequences. (Running on oeis4.)