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Numbers k such that every prime dividing k also divides A114707(k-1).
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%I #6 Jun 28 2024 09:15:53

%S 7,11,13,15,19,21,23,25,27,29,50,64,100,150,162,216,243,384,388,567,

%T 576,625,832,841,873,1024,1029,1176,1215,1528,1536,1856,2187,3185,

%U 3712,4096,4374,5831,6400,6498,8192,8208,8624,9800,10240,10692,11933,14336,15936,16807,17250,18954,19683,21952

%N Numbers k such that every prime dividing k also divides A114707(k-1).

%C Numbers k such that A114707(k) = A114707(k-1).

%C Numbers k such that A114708(k) = 0.

%e a(3) = 13 is a term because 13, the only prime dividing 13, also divides A114707(12) = 13.

%p R:= 1: v:= 1:

%p for n from 2 to 10^6 do

%p v:= v + nops(select(p -> v mod p <> 0, numtheory:-factorset(n)));

%p R:= R,v;

%p od:

%p select(t -> R[t]=R[t-1],[$2..10^6]);

%Y Cf. A114707, A114708.

%K nonn

%O 1,1

%A _Robert Israel_, Jun 27 2024