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%I #21 Feb 16 2025 08:32:50
%S 1,3,9,5,4,8,5,9,7,2,4,7,9,3,0,2,7,3,5,2,2,9,5,0,0,6,6,3,5,6,6,8,8,8,
%T 0,6,8,9,5,4,1,0,3,7,2,8,1,4,4,6,6,1,1,9,0,8,1,7,4,7,2,1,5,6,1,3,5,7,
%U 6,0,8,8,0,3,5,8,6,9,7,7,7,4,6,8,9,8,3,7,8,7,3,0,8,5,2,7,5,4,2,7,9,0
%N Decimal expansion of hard hexagon entropy constant.
%D Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 5.12, p. 343.
%H V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, 2013, p. 69.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HardHexagonEntropyConstant.html">Hard Hexagon Entropy Constant</a>.
%e 1.395485972...
%t RealDigits[N[Root[-32751691810479015985152 + 97143135277377575190528*#1^4 - 73347491183630103871488*#1^6 - 71220809441400405884928*#1^8 + 107155448150443388043264*#1^10 - 72405670285649161617408*#1^12 + 2958015038376958230528*#1^14 + 7449488310131083100160*#1^16 + 797726698866658379776*#1^18 + 2505062311720673792* #1^20 + 2013290651222784*#1^22 + 25937424601*#1^24 & , 2], 200]][[1]] (* _Vaclav Kotesovec_, Apr 03 2014 *)
%Y Cf. A085850, A247413, A066864.
%K nonn,nice,cons,changed
%O 1,2
%A _Eric W. Weisstein_, Jul 05 2003