On Jul 28, 3:34 am, David H Wild <[EMAIL PROTECTED]> wrote: > In article <[EMAIL PROTECTED]>, > [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > > For example, how many ways can you put 492 marbles into > > 264 ordered bins such that each bin has at least 1 marble? > > The answer > > 66189415264331559482776409694993032407028709677550 > > 59629130019289014193777349831417543311612293951363 > > 4124491233746912456893016976209252459301489030 > > has 146 digits. > > What on earth made you think of that question?
Reearch on the Collatz Conjecture. Any Collatz sequence can be described by a non-empty list of integers > 0. Such as [1,1,1,1,1,1,1,1] [1,2,3,4,5,6] [1009873,74396597698765,2,240895734075] I proved that ANY posible list must exist on the Collatz graph infinitely many times. The polynomials derived from such a list identify the first occurence of the set of infinite solutions. For a sequence in 3n+C to be a loop cycle, it is necessary (but not sufficient) for a power of 2 (2**p) to be congruent to a power of 3 (3**q) modulo a divisor of C. For example, the congruence classes of 2**p mod 41 are (1,2,4,5,8,9,10,16,18,20,21,23,25,31,32,33,36,37,39,40) the congruence classes of 3**q mod 41 are (1,3,9,14,27,32,38,40) The only classes they have in common are: {1,9,32,40} so from this table, p or q 2p (mod 41) 3q (mod 41) 0 1 1 1 2 3 2 4 9 3 8 27 4 16 40 5 32 38 6 23 32 7 5 14 8 10 1 9 20 3 10 40 9 11 39 27 12 37 40 13 33 38 14 25 32 15 9 14 16 18 1 17 36 3 18 31 9 19 21 27 20 1 40 only those p,q pairs (such as p=20 q=8) that have matching congruence classes mod 41 can be potential loop cycles in 3n+41. This can be translated to the marble problem by asking how many ways are there to make a list of q non-zero positive integers that sum to p? Of the 50388 ways, 8 of them have integer solutions and because these 8 are cyclic permutaions, they represent the same loop cycle [2,1,3,1,2,1,1,9] 1 [1,3,1,2,1,1,9,2] 11 [3,1,2,1,1,9,2,1] 37 [1,2,1,1,9,2,1,3] 19 [2,1,1,9,2,1,3,1] 49 [1,1,9,2,1,3,1,2] 47 [1,9,2,1,3,1,2,1] 91 [9,2,1,3,1,2,1,1] 157 To actually answer you question, there is a known loop cycle in 3n+85085 for which p=492 and q=264. If there is one solution, there must be at leats 263 others (the cyclic permutations), but to brute force search for any others would require enumerating the answer to how many ways can 492 marbles be put in 264 bins such that each bin has at least 1 marble. > > -- > David Wild using RISC OS on broadbandwww.davidhwild.me.uk -- http://mail.python.org/mailman/listinfo/python-list