|
| |
|
|
A192987
|
|
Denominator of Sum_{i=0..n-1} B(i)/B(n), where B(i) = A000110(i) are the Bell numbers.
|
|
2
|
|
|
|
1, 1, 1, 5, 5, 13, 203, 877, 1035, 21147, 115975, 339285, 4213597, 27644437, 95449661, 1382958545, 10480142147, 6905405817, 682076806159, 5832742205057, 12931039558843, 474869816156751, 4506715738447323, 22076002927542173, 445958869294805289, 4638590332229999353
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
0,4
|
|
|
LINKS
|
|
|
|
EXAMPLE
|
0, 1, 1, 4/5, 3/5, 6/13, 76/203, 279/877, 289/1035, 5296/21147, 26443/115975, ...
|
|
|
MATHEMATICA
|
Table[Denominator[Sum[BellB[j], {j, 0, n-1}]/BellB[n]], {n, 0, 30}] (* G. C. Greubel, Jul 25 2019 *)
|
|
|
PROG
|
(PARI) bell(n)=sum(k=0, n, stirling(n, k, 2));
vector(30, n, n--; denominator( sum(j=0, n-1, bell(j))/bell(n)) ) \\ G. C. Greubel, Jul 25 2019
(Magma) [1] cat [Denominator((&+[Bell(j): j in [0..n-1]])/Bell(n)): n in [1..30]]; // G. C. Greubel, Jul 25 2019
(Sage) [denominator(sum(bell_number(j) for j in (0..n-1))/bell_number(n)) for n in (0..30)] # G. C. Greubel, Jul 25 2019
(GAP) List([0..30], n-> DenominatorRat(Sum([0..n-1], j-> Bell(j))/Bell(n) )); # G. C. Greubel, Jul 25 2019
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn,frac
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
