OFFSET
1,1
COMMENTS
If the twin prime conjecture is true, this sequence has infinitely many pairs of terms with difference at most 3.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = A100464(n) - 1.
EXAMPLE
25 is excluded because it is a multiple of 4+1; 26 is not a multiple of 3,5,8,...,23 so it remains in the sequence.
PROG
(PARI) has(n)=fordiv(n, d, if(mapisdefined(m, d-1), return(0))); 1
first(n)=local(m=Map(Mat([2, 0]))); my(t=3); while(#m<n, while(!has(t++), ); mapput(m, t, 0)); Mat(m)[, 1]~ \\ Charles R Greathouse IV, Sep 16 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
Drake Thomas, Sep 15 2015
STATUS
approved