2475880078570760549798248448

9903520314283042199192993792

19807040628566084398385987584

39614081257132168796771975168

158456325028528675187087900672

633825300114114700748351602688

535301200456458802993406410752

24623855220997104937696694894592

Its wrong answer jasimp the answer is:
2141204801825835211973625643008

4282409603651670423947251286016
On the keyboard I accidentally hit *23, the 3 is right next to the enter button.

17129638414606681695789005144064

68518553658426726783156020576256

Its going beyond range now...windows calc shows this result:
1.3703710731685345356631204115251e+32

This is that shown out the whole way.
137037107316853453566312041152512
Then doubled
274074214633706907132624082305024

Its not '512' in last its 513
in which method you are calculating ?

It is 137037107316853453566312041152512 I just used python to multiply by two.
next
274074214633706907132624082305024

There should have been another 8 on the end of yours.
1096296858534827628530496329220096

Its resulted from windows calculator...i will check it.

2192593717069655257060992658440192

LOL...windows calc doesnt support this range..!!!!!!!

4385187434139310514121985316880384
I can keep going just about forever.