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%I #9 Aug 06 2015 07:45:41
%S 29,33,93,217,341,961,2821,7409,8973,53625,94325,225169,470517,
%T 1349089,4076589,22862205,40165377,506257425,918577233,1042701969,
%U 5347778553,76822655445,242180261569,243151045949,835744242025,1398202164821,7718585207745,17886399120625,36628781776125,140199249091321,579641775855025,3110633457224293,9887055813390673
%N Iterates of A234742, starting from value a(0) = 29, with a(1) = A234742(a(0)), a(2) = A234742(a(1)), etc.
%C The sequence reaches its fixed point at a(141) = <term with 103 decimal digits; binary representation 340 bits long> after which the sequence stays constant, a(142) = a(143) = a(144), etc.
%H Antti Karttunen, <a href="/A260729/b260729.txt">Table of n, a(n) for n = 0..142</a>
%F a(0) = 29; for n >= 1, a(n) = A234742(a(n-1)).
%o (PARI)
%o allocatemem((2^29));
%o A234742(n) = factorback(subst(lift(factor(Mod(1, 2)*Pol(binary(n)))), x, 2)); \\ After _M. F. Hasler_'s Feb 18 2014 code.
%o iterates_of_A234742(start, filename) = {my(n=start, prev=-1, prevprev=-1, i=0); until((n==prevprev), write(filename, i, " ", n); prevprev = prev; prev = n; n = A234742(n); i++)} \\ Computes b-file up to the second occurrence of the fixed point.
%o iterates_of_A234742(29, "b260729.txt")
%o (Scheme, with memoizing macro definec)
%o (definec (A260729 n) (if (zero? n) 29 (A234742 (A260729 (- n 1)))))
%Y Cf. A234742, A260712, A260713.
%Y Cf. also A244323, A260735, A260441 for iterations starting from other values.
%K nonn
%O 0,1
%A _Antti Karttunen_, Aug 04 2015
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