[" Let "m=1+1!n=1!+4!-17!+10!+cdots+4c],[" ten's digit to "^(r)n'n]

Let n=1! +4! +7! +. . . +400 ! then ten's digit of n is

If n=1!+4!+7!+......+400! then ten's digit of ln' is

underset is Let n=3^(100) then for n the value of ten's digit

Let a = 111 cdots 1 (55 digits ) , b=1 + 10 + 10^(2)+ cdots+ 10^(4) c= 1+10^(5) +10^(10)+ 10^(15) + cdots+ 10^(50) then

If n is a one-digit positive integer, what is n? (1) The units digit of 4^n is 4. (2) The units digits of n^4 is n.

Let a_n denote the number of all n-digit positive integers formed by the digits 0, 1, or both such that no consecutive digits in them are 0. Let b_n= The number of such n-digit integers ending with digit 1 and c_n= Then number of such n-digit integers with digit 0. The value of b_6 is

Let n denote the number of all n-digit positive integers formed by the digits 0, 1 or both such that no consecutive digits in them are 0. Let b_n = the number of such n-digit integers ending with digit 1 and c_n = the number of such n-digit integers ending with digit 0. The value of b_6 , is