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%I A143314 #13 Sep 04 2023 01:44:12
%S A143314 0,0,0,0,40,1844,41584,611340,6588116,55482100,380126920,2177910310,
%T A143314 10644616240,45049914588,167011924492,547315800984,1597026077496,
%U A143314 4173458163098,9813490226056,20841357619302,40096048882028
%N A143314 Number of hands of n cards containing a straight flush (for n=1 to 52).
%C A143314 With a regular deck of 52 playing cards (4 suits of 13 cards: 23456789TJQKA) a "straight flush" consists of 5 cards of the same suit with consecutive values. The ace (A) is considered to come either before the deuce (2) or after the king (K).
%C A143314 The first terms of the sequence are zero because there are no straight flushes in a hand of fewer than 5 cards.
%H A143314 Gerard P. Michon, Aug 06 2008, <a href="/A143314/b143314.txt">Table of n, a(n) for n = 1..52</a>
%H A143314 G. P. Michon, <a href="http://www.numericana.com/answer/counting.htm#stud26">q-Card Poker</a>.
%H A143314 Brian Wu and Chai Wah Wu, <a href="https://arxiv.org/abs/2309.00011">Big Two and n-card poker probabilities</a>, arXiv:2309.00011 [math.HO], 2023.
%F A143314 The generating function is a polynomial: (1+x)^52 - ((1+x)^13 - x^5(1+x)(10 + 61x + 156x^2 + 215x^3 + 169x^4 + 65x^5 + 12x^6 + x^7))^4.
%e A143314 a(5) = 40 because each suit allows 10 straight flushes (2 of which contain an ace).
%e A143314 a(44) = 752538149 = C(52,44) - 1 because there's only one way to avoid a straight flush with 44 cards (namely, 2346789JQKA in every suit).
%e A143314 a(45) = 133784560 = C(52,45) because every hand of 45 cards (or more) includes a straight flush.
%e A143314 a(52) = 1 because there's only one "hand" of 52 cards.
%Y A143314 Cf. A002761, A002806, A002834, A002879.
%K A143314 fini,full,nonn
%O A143314 1,5
%A A143314 _Gerard P. Michon_, Aug 06 2008

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