OFFSET
1,2
FORMULA
Logarithmic transform of A318398.
EXAMPLE
The a(2) = 6 triples:
{{1},{2}} {{1},{2}} {{1,2}}
{{1},{2}} {{1,2}} {{1},{2}}
{{1},{2}} {{1,2}} {{1,2}}
{{1,2}} {{1},{2}} {{1},{2}}
{{1,2}} {{1},{2}} {{1,2}}
{{1,2}} {{1,2}} {{1},{2}}
MATHEMATICA
nn=20;
Table[n!*SeriesCoefficient[Log[1+Sum[x^k/k!*Sum[StirlingS1[k, i]*BellB[i]^3, {i, 0, k}], {k, nn}]], {x, 0, n}], {n, nn}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Aug 25 2018
STATUS
approved