A177800 -id:A177800 - cp's OEIS frontend

A177798 First primes of record chains of consecutive primes such that all of them are odious (A027697).

2, 7, 167, 199, 6271, 12227, 168713, 579907, 5937157, 6829751, 8059943, 66858173, 167857663, 661416709, 2322857987, 12012698381, 14641587607, 26304771553, 49671709081, 1244930533403, 1922085626009

Offset: 1

Vladimir Shevelev, Dec 12 2010

The corresponding record lengths are: 1,3,6,9,11,15, etc. (A177800).

Cf. A177748 (evil version), A000069, A001969, A027697, A027699, A177800.

back(p,k)=while(k--,p=precprime(p-1));precprime(p-1)
r=s=0;forprime(p=2,1e9,if(hammingweight(p)%2,s++,if(s>r,r=s;print1(back(p,r)", "));s=0)) \\ Charles R Greathouse IV, Mar 29 2013

More terms from D. S. McNeil, Dec 12 2010

a(20)-a(21) from Amiram Eldar, Dec 09 2020

A177801 Record lengths of chains of consecutive evil primes, starting with A177748(n).

Original entry on oeis.org

2, 3, 5, 7, 8, 12, 16, 20, 23, 25, 26, 30, 31, 32, 34, 38, 39, 40, 41, 42, 44

Offset: 1

Vladimir Shevelev, Dec 12 2010

In contrast to the sequence of all positive integers, where the length of every chain of consecutive evil numbers cannot exceed 2, we conjecture that for the sequence of primes such length is not bounded with growth of n.

Cf. A177800 (odious version), A177748, A177798, A000069, A001969, A027697, A027699.

{l=0;r=0; forprime( p=1, default(primelimit), if( bittest( norml2(binary(p)),0), l>r & print1(r=l ", "); l & l=0, l++))} \\ M. F. Hasler, Dec 12 2010

Extended by D. S. McNeil, Dec 12 2010

a(18)-a(21) from Amiram Eldar, Dec 09 2020

cp's OEIS Frontend

A177798 First primes of record chains of consecutive primes such that all of them are odious (A027697).

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