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A135149
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A binomial recursion : a(n)=p(n) (see comment).
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5
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1, 5, 36, 304, 2973, 33156, 415962, 5803307, 89172846, 1496858836, 27258427263, 535299208890, 11277600621714, 253741796354921, 6072776118043704, 154050364873902628, 4128986249628307077, 116598919802471049936
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Let z(1)=x and z(n)=1+sum(k=1,n-1,(3+binomial(n,k))*z(k)), then z(n)=p(n)*x+q(n).
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REFERENCES
| B. Cloitre, Binomial recursions, Pi and log2, in preparation 2007
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FORMULA
| Lim n-->infty p(n)/q(n)=(15*Pi-22)/(52-15*Pi)=5.1524450418835554775446337...
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PROG
| (PARI) r=1; s=3; v=vector(120, j, x); for(n=2, 120, g=r+sum(k=1, n-1, (s+binomial(n, k))*v[k]); v[n]=g); z(n)=v[n]; p(n)=polcoeff(z(n), 1); q(n)=polcoeff(z(n), 0); a(n)=p(n);
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CROSSREFS
| Cf. A135147, A135148, A135150, A135074, A135075.
Sequence in context: A052203 A027331 A091161 * A067305 A000806 A127132
Adjacent sequences: A135146 A135147 A135148 * A135150 A135151 A135152
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KEYWORD
| nonn
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AUTHOR
| Benoit Cloitre (benoit7848c(AT)orange.fr), Nov 20 2007
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