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Search: id:A165940
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| A165940 |
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G.f.: Sum_{n>=0} a(n)*x^n/2^(n^2+n) = exp( Sum_{n>=1} x^n/[n*2^(n^2)] ). |
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1
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| 1, 2, 10, 152, 7684, 1352096, 852120928, 1960591940480, 16697154282192928, 531801639623740649984, 63854080509077223292639744, 29089348119991257994736112048128
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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Conjectured to consist entirely of integers.
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EXAMPLE
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G.f.: 1 + 2*x/2^2 + 10*x^2/2^6 + 152*x^3/2^12 + 7684*x^4/2^20 +...
= exp( x/2 + x^2/(2*2^4) + x^3/(3*2^9) + x^4/(4*2^16) +... ).
Evaluated at x=1:
Sum_{n>=0} a(n)/2^(n^2+n) = 1.7021716250154556344906565654972646...
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PROGRAM
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(PARI) {a(n)=2^(n^2+n)*polcoeff(exp(sum(m=1, n+1, 2^(-m^2)*x^m/m)+x*O(x^n)), n)}
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CROSSREFS
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Cf. A155200.
Sequence in context: A152804 A060595 A086619 this_sequence A007080 A134088 A076659
Adjacent sequences: A165937 A165938 A165939 this_sequence A165941 A165942 A165943
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KEYWORD
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nonn
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AUTHOR
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Paul D. Hanna (pauldhanna(AT)juno.com), Oct 01 2009
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