e = 2.7182818284 5904523536 0287471352 6624977572 4709369995 9574966967 6277240766 3035354759 4571382178 5251664274 ...

e = lim _{(n -> 0)} (1 + n)^{^(1/n)}   or   e = lim _{(n -> )} (1 + 1/n)^{^n}

e = 1 / k!

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