OFFSET
1,1
COMMENTS
Seems identical to A054546. Each odd prime arises once or twice!?
First differences of A018252 (positive nonprime numbers). Including 0 gives A054546. Removing 1 gives A073783. - Gus Wiseman, Sep 15 2024
LINKS
Harry J. Smith, Table of n, a(n) for n = 1..1000
MATHEMATICA
t=Table[Prime[w-PrimePi[w]], {w, a, b}] Table[Count[t, Prime[n]], {n, c, d}]
Differences[Select[Range[100], !PrimeQ[#]&]] (* Gus Wiseman, Sep 15 2024 *)
PROG
(PARI) { p=1; f=2; m=1; for (n=1, 1000, a=0; p=nextprime(p + 1); while (p==f, a++; m++; f=prime(m - primepi(m))); write("b065310.txt", n, " ", a) ) } \\ Harry J. Smith, Oct 16 2009
CROSSREFS
For twin 2's see A169643.
Other families of numbers and their first-differences:
KEYWORD
nonn
AUTHOR
Labos Elemer, Oct 29 2001
STATUS
approved