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A248380 a(n) = 1 if first player in Sylver coinage game can force a win by choosing n as the first number, otherwise a(n) = 2. 0
2, 2, 2, 2, 1, 2, 1, 2, 2, 2, 1, 2, 1, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Although a(16) is not known, a few later terms are known. For example a(17)=1.
J. H. Conway offered $1000 for the value (with proof) of a(16).
LINKS
Joshua Fallon, Kirsten Hogenson, Lauren Keough, Mario Lomelí, Marcus Schaefer, and Pablo Soberón, A Note on the Maximum Rectilinear Crossing Number of Spiders, arXiv:1808.00385 [math.CO], 2018.
Aleksandar Jurišić and Janoš Vidali, No strongly regular graph is locally Heawood, Chebyshevskii Sbornik (2020) Vol. 20, No. 2, 199-206.
OEIS50 DIMACS Conference on Challenges of Identifying Integer Sequences, Problem Session 2, Oct 10 2014, J. H. Conway, Five $1000 Problems (starting at about 06.44). This sequence is mentioned in the first problem.
Tal Schuster, Ashwin Kalyan, Oleksandr Polozov, and Adam Tauman Kalai, Programming Puzzles, arXiv:2106.05784 [cs.LG], 2021.
Wikipedia, Sylver coinage
Sa’ar Zehavi and Ivo Fagundes David de Oliveira, Not Conway's 99-Graph Problem, research paper, Department of Computer Science, Technion, Sep 15 2017.
CROSSREFS
Sequence in context: A236472 A175357 A232800 * A090044 A036238 A318723
KEYWORD
nonn,more,hard
AUTHOR
N. J. A. Sloane, Oct 10 2014
STATUS
approved

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Last modified March 29 08:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)