A228003 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

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

FORMULA

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

CROSSREFS