$15\equiv 15 mod(1000)$
$15^{2}\equiv 225 mod(1000)$
$15^{3}\equiv 375 mod(1000)$
$15^{4}\equiv 625 mod(1000)$
$15^{5}\equiv 375 mod (1000) $
...
Bundan sonraki her tek us de sonuc 375 ,her tek us de snc 625 cikmaktadr 2015 tek olduundan son uc basamagi 375 tir