A177748 First primes of record chains of consecutive primes such that all of them are evil (A027699).

3, 257, 337, 4423, 4919, 30431, 66841, 514271, 14490383, 231234569, 325923613, 640085473, 1600993259, 7180164577, 8069913503, 86933359951, 284331217637, 1128352801153, 1209935587291, 2454267258251, 2945783287813

Offset: 1

Author

Vladimir Shevelev, Dec 12 2010

Keywords

• nonn
• base
• more

Comments

The first lengths of such chains of primes are: 2, 3, 5, 7, 8, 12, 16, ..., cf. A177801.

Examples

			257 is the first evil prime followed by two consecutive primes (263,269) which are also evil. Thus it is record length 3.
		

Crossrefs

Cf. A001969, A000069, A027697, A027699, A177798 (odious version), A177801.

Programs

PARI

{l=0;sp=0;r=0; forprime( p=1, default(primelimit), if( norml2(binary(p))%2, l>r & !print1(sp", ") & r=l; l & l=0, l || sp=p; l++))} \\ M. F. Hasler, Dec 12 2010

Extensions

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

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