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A245274 Composite terms in sequence {A243937(n)-1}. 0

%I #11 Jul 18 2014 21:43:52

%S 35,65,77,95,119,121,125,143,155,161,185,187,203,209,215,217,221,245,

%T 247,275,287,289,299,305,323,329,335,341,365,371,377,395,407,413,425,

%U 427,437,455,473,485,497,515,517,527,529,533,539,545,551,575,581,583,605

%N Composite terms in sequence {A243937(n)-1}.

%C See comment in A243937.

%C If prime p is not in A062326, then p^2 is in the sequence.

%C If p>3 and p,p+2 are twin primes, then p*(p+2) is in the sequence. Indeed, it can be shown that in this case (p+1)^2 is in A243937. lpf((p+1)^2-1)=p while lpf((p+1)^2-3)=3, since for lesser p>3 of twin prime p+1==0(mod 6).

%Y Cf. A245272, A243937, A245024.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, Jul 16 2014

%E More terms from _Peter J. C. Moses_, Jul 16 2014

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)