A232992 Let b(i) = A134204(i) and c(n) = A133242(n); a(n) is the number of primes p <= c(n) such that p is not in {b(0), b(1), ..., b(c(n)-1)}.
1, 1, 2, 1, 1, 2, 2, 3, 2, 1, 2, 3, 6, 7, 6, 7, 7, 7, 6, 5, 7, 12, 11, 10, 10, 9, 10, 12, 11, 12, 11, 10, 9, 9, 8, 8, 8, 9, 8, 8, 8, 7, 10, 16, 16, 16, 19, 18, 17, 16, 15, 15, 16, 16, 17, 16, 15, 16, 16, 19, 19, 20, 20, 19, 18, 17, 16, 17, 20, 19, 20, 19, 18, 18, 19, 23, 24, 23, 25, 24, 25, 27, 26, 27, 27, 26, 25, 25
Offset: 1
Keywords
Examples
Terms b(0) through b(12) of A134202 are (ignore the periods, which are just for alignment):
i:... 0, 1, 2, 3,. 4,. 5,. 6,. 7,. 8,. 9, 10, 11, 12
b(i): 2, 3, 5, 7, 13, 17, 19, 23, 41, 31, 29, 37, 11
c(1) = 12 is the first i for which b(i)<i.
Then a(1) is the number of primes p <= 12 that are not in the set {b(0), ..., b(11)} = {2, 3, 5, 7, 13, 17, 19, 23, 41, 31, 29, 37}.
Only p = 11 is missing, so a(1)=1.
Links
- David Applegate, Table of n, a(n) for n = 1..10000
- David Applegate, C++ Program
- David Applegate, Notes on programs and output
- David Applegate, The first 106394 lines of output. The first 3 columns give the first 106394 terms of A133242, A133243 and A232992 (the present sequence), and establish that at least 800 million terms of A134204 exist.
Comments