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1512
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location Bellevue, WA
age 77
visits member for 4 years, 3 months
seen May 30 at 3:28

Nov
30
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
@Hans: Thanks for that. An extremely useful clarification for me.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
@Hans: Ha! I see our comments crossed each other. I'll look at that other question.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
But now I sort of do, because I just read the Wikipedia article en.wikipedia.org/wiki/Hyperbolic_function . Also Hans, thanks for the link to Inverse Symbolic Calculator. Very interesting.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
Well, I have to confess that I don't even know what cosh(x) means.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
Ah, you guys are amazing. Now, rather than asking for a proof (although I'm glad to see it), I wanted to know how you knew that my series could be taken apart into those 2 pieces, and that the limit is (e + 1/e)/2.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
@Americo: There seems to be something wrong -- I see only what is to me strange code.
Nov
29
comment What is limit of $\sum \limits_{n=0}^{\infty}\frac{1}{(2n)!} $?
@Hans: Tell me a bit more? Why is it that? Thanks.
Nov
15
comment True?: Let $(n, m)$ be an arbitrary Amicable Pair. Then $n$ is odd iff its last digit is $5$
Thanks. Good article. It's coming back, slowly.
Nov
15
comment True?: Let $(n, m)$ be an arbitrary Amicable Pair. Then $n$ is odd iff its last digit is $5$
Damn. You're right. Thanks. BTW I'm rusty. Could you spell out the terminology in "not congruent to 5 mod 10"? Thanks.
Nov
15
comment True?: Let $(n, m)$ be an arbitrary Amicable Pair. Then $n$ is odd iff its last digit is $5$
I neglected to say that n < m. The n of the pair (69615, 87633) is odd and ends in '5'.
Nov
15
comment Amicable Pair $(a, b)$: given $a$, what are limits on size of $b$?
Thanks!
Nov
14
comment Amicable Pair $(a, b)$: given $a$, what are limits on size of $b$?
What is that exponent of e?