Find the sum of the first 10,000 terms of the arithmetic sequence beginning with 246, 261, and 276....

Is this the answer? My friend told me it was
A(n) = 15n + 231
......... n
S(n) = ∑ (15n + 231) = 15 (1/2) n (n+1) + 231 n
......... k=1

S(10000) = 15 (1/2) (10000) (10001) + 231 (10000) = 752385000

Question

Find the sum of the first 10,000 terms of the arithmetic sequence beginning with 246, 261, and 276.... 

Is this the answer? My friend told me it was 
A(n) = 15n + 231
......... n
S(n) = ∑ (15n + 231) = 15 (1/2) n (n+1) + 231 n
......... k=1

S(10000) = 15 (1/2) (10000) (10001) + 231 (10000) = 752385000

anonymous · Answer

anyone?

amistre64 · Answer

what the common difference between terms?