%I A090699
%S A090699 2,1,7,3,2,5,4,3,1,2,5,1,9,5,5,4,1,3,8,2,3,7,0,8,9,8,4,0,4,3,8,2,2,3,7,
%T A090699 2,2,9,0,6,7,1,1,3,2,9,1,3,1,6,6,0,8,5,6,7,4,9,1,7,5,7,5,8,9,6,7,0,5,9,
%U A090699 6,6,1,7,2,6,6,4,4,4,6,8,2,0,3,7,8,5,7,2,7,8,3,8,3,1,7,6,5,1,0,2,6,6,4
%N A090699 Decimal expansion of the Erdos-Szekeres constant zeta(3/2)/zeta(3).
%C A090699 Let N(x) denotes the number of 2-full integers not exceeding x. Then 
               limit x ->infty N(x)/sqrt(x)=zeta(3/2)/zeta(3). Also related to Niven's 
               constant.
%D A090699 S. R. Finch, Mathematical Constants, Cambridge, 2003, pp. 112-114.
%D A090699 S. W. Golomb, Powerful numbers, Amer. Math. Monthly, Vol. 77 (1970), 
               848-852.
%F A090699 Product_{p prime} (1+1/p^(3/2)) = zeta(3/2)/zeta(3) - T. D. Noe (noe(AT)sspectra.com), 
               May 03 2006
%e A090699 zeta(3/2)/zeta(3) = 2.17325431251955413823708984...
%t A090699 RealDigits[N[Zeta[3/2]/Zeta[3],150]] - T. D. Noe (noe(AT)sspectra.com), 
               May 03 2006
%Y A090699 Cf. A001694 (powerful numbers), A102834 (non-square powerful numbers).
%Y A090699 Cf. A033150.
%Y A090699 Sequence in context: A136535 A091370 A125697 this_sequence A120903 A021050 
               A115629
%Y A090699 Adjacent sequences: A090696 A090697 A090698 this_sequence A090700 A090701 
               A090702
%K A090699 cons,nonn
%O A090699 1,1
%A A090699 Benoit Cloitre (benoit7848c(AT)orange.fr), Jan 14 2004
%E A090699 Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion 
               of Andrew Plewe, May 16 2007