OFFSET
1,3
LINKS
Eric Weisstein's World of Mathematics, Product Rule.
FORMULA
EXAMPLE
................. 0
.............. 1 ... 4
........... 1 ... 5 ... 6
........ 4 .. 12 .. 16 .. 32
..... 1 ... 7 ... 8 .. 24 .. 10
.. 5 .. 16 .. 21 .. 44 .. 31 .. 60
1 ... 9 .. 10 .. 32 .. 12 .. 41 .. 14.
MATHEMATICA
ader[n_] := ader[n] =Switch[n, 0 | 1, 0, _, If[PrimeQ[n], 1, Sum[Module[{p, e}, {p, e} = pe; n e/p], {pe, FactorInteger[n]}]]];
T[n_, k_] := ader[n k];
Table[T[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* Jean-François Alcover, Sep 21 2021 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Reinhard Zumkeller, Jun 10 2003
STATUS
approved