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A260729 Iterates of A234742, starting from value a(0) = 29, with a(1) = A234742(a(0)), a(2) = A234742(a(1)), etc. 5

%I

%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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Last modified October 15 04:33 EDT 2019. Contains 328026 sequences. (Running on oeis4.)