A092742 - OEIS

%I #38 Dec 08 2024 12:23:49

%S 1,0,1,3,2,1,1,8,3,6,4,2,3,3,7,7,7,1,4,4,3,8,7,9,4,6,3,2,0,9,7,2,7,6,

%T 3,8,9,0,4,3,5,8,7,7,4,6,7,2,2,4,6,5,4,8,8,4,5,6,0,9,0,3,1,8,9,4,1,7,

%U 3,1,2,0,9,6,2,2,3,5,4,4,1,1,9,1,2,0,9,2,7,3,9,2,5,6,2,1,8,3,7,6,1,3,6,2,2

%N Decimal expansion of 1/Pi^2.

%C The asymptotic density of squarefree numbers that are divisible by 5. - _Amiram Eldar_, Mar 25 2021

%D Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 3.6.1, p. 220.

%H S. Ramanujan, <a href="http://ramanujan.sirinudi.org/Volumes/published/ram17.html">Some formulas in the analytic theory of numbers</a> Messenger of Mathematics, XLV, 1916, pp. 81-84, Formula (3).

%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>

%e 0.101321183642337771443879463209727638904358774672246548845609...

%t RealDigits[N[1/Pi^2,200]][[1]] (* _Vladimir Joseph Stephan Orlovsky_, May 27 2010 *) (* Corrected by _Harvey P. Dale_, Sep 21 2024. *)

%t realDigitsRecip[Pi^2] (* The realDigitsRecip program is at A021200 *) (* _Harvey P. Dale_, Sep 21 2024 *)

%o (PARI) c=Pi^-2; a=eval(vecextract(Vec(Str(c)),"3..-2"))  \\ _M. F. Hasler_, Sep 16 2011

%Y Cf. A000796 (Pi), A002388 (Pi^2), A091925 (Pi^3), A092425 (Pi^4), A092731 (Pi^5), A092732 (Pi^6), A092735 (Pi^7), A092736 (Pi^8).

%Y Cf. A049541 (1/Pi), A092743 (1/Pi^3), A092744 (1/Pi^4), A092745 (1/Pi^5), A092746 (1/Pi^6), A092747 (1/Pi^7), A092748 (1/Pi^8).

%K cons,nonn

%O 0,4

%A _Mohammad K. Azarian_, Apr 12 2004