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A370607 2-valuations of terms of A370606.

%I A370607 #14 Feb 23 2024 21:39:43
%S A370607 0,1,2,4,5,6,8,9,12,13,16,18,19,20,21,22,25,26,27,30,31,33,36,37,39,
%T A370607 41,42,43,44,45,46,47,48,50,52,55,56,57,59,60,63,66,67,68,69,70,71,75,
%U A370607 77,78,81,82,85,86,87,88,89,92,93,94,95,96,98,99,100,103,104
%N A370607 2-valuations of terms of A370606.
%H A370607 Chai Wah Wu, <a href="/A370607/b370607.txt">Table of n, a(n) for n = 1..2000</a>
%o A370607 (PARI) r=-1;forprime(p=2,10^12,v=valuation(p-1,2);if(v>r,print1(v,", ");r=v));
%o A370607 (Python)
%o A370607 from itertools import count, islice
%o A370607 from sympy import isprime
%o A370607 def A370607_gen(): # generator of terms
%o A370607     a = 1
%o A370607     while True:
%o A370607         for q in count(a,a):
%o A370607             if isprime(q+1):
%o A370607                 yield (b:=q&-q).bit_length()-1
%o A370607                 a = b<<1
%o A370607                 break
%o A370607 A370607_list = list(islice(A370607_gen(),30)) # _Chai Wah Wu_, Feb 23 2024
%K A370607 nonn
%O A370607 1,3
%A A370607 _Joerg Arndt_, Feb 23 2024
%E A370607 a(21)-a(67) from _Chai Wah Wu_, Feb 23 2024