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%I #7 May 25 2021 01:38:07
%S 4,5,6,7,8,15,18,19,26,33,44,50,64,69,74,115,138,139,150,151,161,170,
%T 208,213,218,232,233,237,246,258,275,289,290,303,309,310,311,333,334,
%U 340,352,353,360,369,376,405,412,441,483,489,495,502,503,507,514,529,610,615,633,638,645,648,658
%N Numbers k such that A101203(k) is prime.
%C Numbers k such that the sum of nonprimes <= k is prime.
%C If p is prime then p is a member if and only if p-1 is a member.
%H Robert Israel, <a href="/A344580/b344580.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3) = 6 is a member because A101203(6) = 1+4+6 = 11 is prime.
%p s:= proc(n) option remember; if isprime(n) then procname(n-1) else procname(n-1)+ n fi end proc:
%p s(1):= 1:
%p select(n -> isprime(s(n)), [$1..1000]);
%Y Cf. A101203, A228102.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, May 23 2021
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