A228003 Places of records of A227321.

0, 4, 11, 13, 19, 31, 43, 61, 73, 103, 109, 139, 151, 181, 193, 199, 211, 223, 229, 241, 271, 283, 313, 349, 379, 409, 421, 433, 439, 463, 523, 571, 601, 613, 619, 631, 643, 649

Offset: 1

Author

Vladimir Shevelev, Aug 07 2013

Keywords

• nonn

Comments

Records of A227321 are 3, 4, 5, 8, 11, 17, 23, 32, 38,....

The first 3 nonprimes are a(1)=0, a(2)=4, a(38)=649.

The sequence contains all greaters of twin primes more than 7 (see A006512).

Links

• Peter J. C. Moses, Table of n, a(n) for n = 1..2000

Crossrefs

Cf. A227321, A006512.

Formula

For n>=4, A227321(a(n)) = (a(n) + 3)/2.

Extensions

More terms from Peter J. C. Moses, Aug 07 2013