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Numbers k such that A248891(k) = 1.
3

%I #12 Nov 28 2020 06:35:23

%S 1,2,3,4,5,20,29,30,2059,5987,7119,20165,151819,14984624,105181798

%N Numbers k such that A248891(k) = 1.

%C If k is in {1, 2, 3, 4, 29, ...} then both numbers k and k+1 are in the sequence.

%o (PARI) lista(nn) = {my(c=0, q=r=5, s=3, t); forprime(p=9, nn, if(p-2==q, if((t=s^(1+1/c++))>r && t<q, print1(c, ", ")); s=r; r=q); q=p); } \\ _Jinyuan Wang_, Nov 28 2020

%Y Cf. A001359, A248891, A248902, A248903.

%K nonn,more

%O 1,2

%A _Jahangeer Kholdi_ and _Farideh Firoozbakht_, Nov 22 2014

%E a(13)-a(15) from _Jinyuan Wang_, Nov 28 2020