Help Lakshya!

Lakshya is learning number theory. He reads about the Möbius function : μ : N Z \mu : \mathbb{N} \longrightarrow \mathbb{Z} defined by μ ( 1 ) = 1 \mu(1) = 1 and

μ ( n ) = d n d n μ ( d ) \large{\mu \left( n \right) =-\sum _{ d|n\\ d\neq n }^{ }{ \mu \left( d \right) } }

for n>1. However, Lakshya doesn't like negative numbers, so he invents his own function: the Lakshyaous function δ : N N \delta : \mathbb{N} \longrightarrow \mathbb{N} defined by the relations δ ( 1 ) = 1 \delta (1)=1 and

δ ( n ) = d n d n δ ( d ) \large{\delta \left( n \right) =\sum _{ d|n\\ d\neq n }^{ }{ \delta \left( d \right) } }

for n > 1. So he asks his teacher Otto Bretscher to help solve the below question. Otto Bretscher gave him hint but he cannot solve. Help Lakshya determine the value of 1000 p + q 1000p+q , where p p and q q are relatively prime positive integers satisfying:

p q = k = 0 δ ( 15 k ) 15 k \large{\frac { p }{ q } =\sum _{ k=0 }^{ \infty }{ \frac { \delta \left( { 15 }^{ k } \right) }{ { 15 }^{ k } } } }


The answer is 11007.

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