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 A275432 P-positions for the subtraction game whose allowed moves are the practical numbers (A005153). 1
 0, 3, 10, 13, 44, 47, 102, 105, 146, 149, 232, 235, 636, 639, 814, 817, 950, 953, 1208, 1211, 2994, 2997, 4922, 4925, 4996, 4999, 6748, 6751, 8026, 8029, 8478, 8481, 12092, 12095, 14004, 14007, 31934, 31937, 35824, 35827, 41568, 41571, 46118, 46121, 60056, 60059, 62530, 62533, 106986, 106989 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS According to a general theorem of Golomb (1966) on subtraction games, this sequence is infinite, and more strongly (because of known results on the density of A005153) the number of terms below any given n is at least logarithmic in n. LINKS S. W. Golomb, A mathematical investigation of games of "take-away", J. Combinatorial Theory, 1 (1966), 443-458. EXAMPLE For instance, 10 is a P-position because each of the available moves (subtracting 1, 2, 4, 6, or 8 to yield 9, 8, 6, 4, or 2) can be countered: from 8, 6, 4, or 2, it is possible to win by moving directly to 0 and from 9 it is possible to win by subtracting 6 and moving to the smaller P-position 3. CROSSREFS Cf. A030193. Sequence in context: A285181 A042331 A082975 * A041985 A081519 A041121 Adjacent sequences: A275429 A275430 A275431 * A275433 A275434 A275435 KEYWORD nonn AUTHOR David Eppstein, Nov 20 2016 STATUS approved

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Last modified March 31 06:29 EDT 2023. Contains 361634 sequences. (Running on oeis4.)