A242730 Decimal expansion of the Conway-Guy constant, a constant associated with Erdős' sum-distinct set constant.

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

Offset: 0

Author

Jean-François Alcover, May 21 2014

Keywords

• nonn
• cons

Examples

			0.23512528481117486563558817439187900988...
		

References

• J. H. Conway and R. K. Guy, “Sets of Natural Numbers with Distinct Sums,” Notices Amer. Math. Soc., vol. 15, 1968.
• Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 2.28, p. 189.

Links

• W. F. Lunnon, Integer sets with distinct subset-sums, Math. Comp. 50 (1988), 297-320.

Crossrefs

Cf. A002083, A005255.

Programs

Mathematica

digits = 100; Clear[v, s]; v[n_] := v[n] = 2*v[n-1] - v[n-1 - Floor[1/2 + Sqrt[2*(n-1)]]]; v[0] = 0; v[1] = 1; s[k_] := s[k] = v[k]/2^k // N[#, digits + 5] &; s[dk = 250]; s[k = 2*dk]; While[RealDigits[s[k], 10, digits] != RealDigits[s[k - dk], 10, digits],  Print["k = ", k]; k = k + dk]; RealDigits[s[k], 10, digits] // First