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# Problem 473

Phigital number base

Let φ be the golden ratio: φ=(1+√5)/2.
Remarkably it is possible to write every positive integer as a sum of powers of φ even if we require that every power of φ is used at most once in this sum.
Even then this representation is not unique.
We can make it unique by requiring that no powers with consecutive exponents are used and that the representation is finite.
E.g: 2=φ+φ−2 and 3=φ2−2

To represent this sum of powers of φ we use a string of 0’s and 1’s with a point to indicate where the negative exponents start.
We call this the representation in the phigital numberbase.
So 1=1φ, 2=10.01φ, 3=100.01φ and 14=100100.001001φ.
The strings representing 1, 2 and 14 in the phigital number base are palindromic, while the string representating 3 is not.
(the phigital point is not the middle character).

The sum of the positive integers not exceeding 1000 whose phigital representation is palindromic is 4345.

Find the sum of the positive integers not exceeding 1010 whose phigital representation is palindromic.

φ进制

（因为小数点并不在数字的中间）。