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A321138
Reduced numbers with multiplicative persistence 10 in base 14.
3
397912927, 5449646691, 7987762047, 8408836868, 8416865813, 14311910772, 95358760419, 95359835871, 119207613951, 119319977811, 178002991683, 181182645587, 268593608191, 780359955604, 781941158165, 802715724229, 985373000485, 986970420491, 1068017311927, 1068025296336
OFFSET
1,1
COMMENTS
Let p_14(n) be the product of the digits of n in base 14. We can define an equivalence relation DP_14 on n by n DP_14 m if and only if p_14(n) = p_14(m); the naming DP_b for the equivalence relation stands for "digits product for representation in base b". A number n is called the class representative number of class n/DP_14 if and only if p_14(n) = p_14(m), m >= n; i.e., the smallest number of that class; it is also called the reduced number.
For any multiplicative persistence, except the multiplicative persistence 2, the set of class representative numbers with that multiplicative persistence is supposed to be finite. Each class representative number represents an infinite set of numbers with the same multiplicative persistence.
If there exists more reduced numbers with multiplicative persistence 10, it will be larger than 14^100.
a(1) = A321135(10).
EXAMPLE
The number 397912927 represented in base 14, with A..D for 10..13 is 3ABBDDDD. Other numbers with the same reduced number are for instance 325BBDDDD or 13ABBDDDD; or any number obtained by permutation of the digits of those numbers.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
A.H.M. Smeets, Oct 28 2018
STATUS
approved