The Counting Thread

[BrilloPad]

you are a bit late.

what is the fourth?

http://en.wikipedia.org/wiki/Perfect_number

Euclid discovered that the first four perfect numbers are generated by the formula 2n−1(2n − 1):

for n = 2: 21(22 − 1) = 6
for n = 3: 22(23 − 1) = 28
for n = 5: 24(25 − 1) = 496
for n = 7: 26(27 − 1) = 8128.

[BrilloPad]

506

[BrilloPad]

507

[BrilloPad]

508

[Pinto]

509

[Pinto]

510

[Pinto]

511

[AndyGarbs]

512

number 217 today

[moorfield]

513 - harshad number

514 - nontotient number

[AndyGarbs]

515

If we get to 590 we would have doubled the post count in 1 day

gotta be a record