Let's play the boom-game! [duplicate]

back ground

in my country we had a silly game as kids, called 7-BOOM! The rules are really simple. We counted 1,2,3... each time we had a number that one of his digit is 7 or it is a multiply of 7 we said "BOOM" instead of this number, otherwise we were out of the game! Lets create our version to this game!

explanation

we will play n-boom in the range [1,a].

input- An integer "n" that represent the "boom-number" and another integer "a" that represent our range. Let assume that n is a positive one-digit integer and that a is an integer such that a>1 and both inputs are valid inputs.

output - Number of booms in our game.

examples

(~ represent boom)

a     n             string                        output

10    2       1,~,3,~,5,~,7,~,9,~                    5

10    3       1,2,~,4,5,~,7,8,~,10                   3

100   1       ~,~,~,~,~,~,~...~,~                    100

32    2     1,~,3,~...19,~,~,~,~,~,~,~,~,~,~,~,31,~   21


This is a code-golf, so the fewest bytes code is the winner! Have fun :)