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%I #19 Sep 06 2021 16:07:55
%S 7,15,23,31,39,63,79,95,127,175,207,255,511,543,607,767,1023,1279,
%T 2047,4095,4423,5135
%N Positions of decreases in sequence A061712 (related to Hamming weights of primes).
%C Is the sequence infinite?
%C All terms listed are of the form == 7 (mod 8). Is there a reason for this phenomenon?
%C Conjecture: The numbers 2^k-1 for k > 2 are terms. - _Chai Wah Wu_, Sep 02 2021
%F {n : A061712(n) < A061712(n-1)}.
%Y Cf. A061712.
%K nonn,more,base
%O 1,1
%A _Vladimir Shevelev_, May 13 2010
%E a(20)-a(22) from _Chai Wah Wu_, Sep 06 2021