OFFSET
0,3
COMMENTS
Number of p-adic cyclotomic type levels in A_n-1 or SU(n).
FORMULA
a(n) = pi(n^2) + 2 = A038107(n) + 2, n > 1. [Charles R Greathouse IV, Nov 07 2011]
EXAMPLE
SU(5) at n^2-1=24 is exactly inside SU(9) at n^2-1=80.
MATHEMATICA
Table[Sum[If[m == 0 || m == 1, 1, If[PrimeQ[m], 1, 0]], {m, 0, n^2 - 1}], {n, 0, 30}]
PROG
(PARI) a(n)=if(n<2, n, primepi(n^2)+2) \\ Charles R Greathouse IV, Nov 07 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula and Gary W. Adamson, Aug 26 2008
STATUS
approved