Integration of an infinite product

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ecpietscheck
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Hey guys, what sup
I need you all to help me in resolving the integral of an infinite product...
i was thinking of perhaps integrating by parts, but when yo do that the integration becomes brutally expansive...
any ideas?
thank you all very much

the variable which is aimed to be integrated is x btw...
 
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  • Integral sign over a product from m = 1 to n of (x^2 + m), set equal to a blank right-hand side.
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You wrote down a finite product. Do you in fact want ##\int \prod_{m=1}^\infty (x^2 + m) \, dx##?
 
for example

(x*x+1)*(x*x+2)*(x*x+3)*(x*x+4) = x^8 + a*x^6 + b*x^4 + c*x^2 + 1*2*3*4

1*2*3*4 = 4!


(x*x+1)*(x*x+2)*(x*x+3)*(x*x+4) = x^8 + 10x^6 + 35x^4 + 50x^2 + 24

Each member must be integrated.

∫ x^8 + 10x^6 + 35x^4 + 50x^2 + 24 dx =

= x^9/9 + 10x^7/7 + 7x^5 +50x^3/3 +24x + C

kamke
 
kamke said:
(x*x+1)*(x*x+2)*(x*x+3)*(x*x+4) = x^8 + 10x^6 + 35x^4 + 50x^2 + 24

Each member must be integrated.
The problem is to get a general formula for those coefficients.

Basically ##\displaystyle \sum_{i,j,...=1, i<j<...}^n i*j*k*...## with 0 to n indices in the sum.
The second sum, for example, sums 1*2+1*3*...+1*n + 2*3+2*4+...+2*n+...
 
MFB, that answer seems a bit unclear
perhaps any other ideas?