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A258192 Denominator of Integral_{x=0..1} Product_{k=1..n} x^k*(1-x^k) dx. 6
6, 420, 72072, 760760, 1266697832400, 783333734619744, 3002950101013562700, 1253414030788528596187200, 27809824888100301666382826331840, 118802724769051077369996224554510800, 2005396188718644499811084404372455793370133120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Limit n->infinity (A258191(n)/a(n))^(1/n) = 0.185155...

The limit is equal to 0.1851552893223595946473132111979542852738... = 1/5.400871904118154152466091119104270052029... (see A258234). - Vaclav Kotesovec, May 24 2015

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 1..49

StackExchange - Mathematica, No response to an infinite limit

EXAMPLE

Product_{k=1..n} x^k*(1-x^k)

n=1 x - x^2

n=2 x^3 - x^4 - x^5 + x^6

n=3 x^6 - x^7 - x^8 + x^10 + x^11 - x^12

Integral Product_{k=1..n} x^k*(1-x^k) dx

n=1 x^2/2 - x^3/3

n=2 x^4/4 - x^5/5 - x^6/6 + x^7/7

n=3 x^7/7 - x^8/8 - x^9/9 + x^11/11 + x^12/12 - x^13/13

For Integral_{x=0..1} set x=1

n=1 1/2 - 1/3 = 1/6, a(1)=6

n=2 1/4 - 1/5 - 1/6 + 1/7 = 11/420, a(2)=420

n=3 1/7 - 1/8 - 1/9 + 1/11 + 1/12 - 1/13 = 293/72072, a(3)=72072

MATHEMATICA

nmax=15; p=1; Table[p=Expand[p*x^n*(1-x^n)]; Total[CoefficientList[p, x]/Range[1, Exponent[p, x]+1]], {n, 1, nmax}] // Denominator

CROSSREFS

Cf. A258191, A258229, A258230, A258234.

Sequence in context: A106206 A174773 A229471 * A273820 A162088 A199253

Adjacent sequences:  A258189 A258190 A258191 * A258193 A258194 A258195

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, May 23 2015

STATUS

approved

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Last modified May 11 14:58 EDT 2021. Contains 343791 sequences. (Running on oeis4.)