A280248 Partial products of A280246 (Product_{d|n} psi(d)).

1, 1, 3, 12, 120, 2160, 45360, 2903040, 235146240, 47029248000, 2586608640000, 4469659729920000, 348633458933760000, 307494710779576320000, 553490479403237376000000, 2267097003635660292096000000, 308325192494449799725056000000

Offset: 1

Author

Jaroslav Krizek, Dec 30 2016

Keywords

• nonn

Comments

psi(n) is the sum of totatives of n (A023896).

Crossrefs

Cf. A023896, A280246, A280247.

Programs

Magma

[&*[&*[&+[h: h in [1..d] | GCD(h,d) eq 1]: d in Divisors(k)]: k in [1..n]]: n in [1..100]]

Mathematica

FoldList[#1 #2 &, Table[Product[Total@ Select[Range@ d, CoprimeQ[d, #] &], {d, Divisors@ n}], {n, 17}]] (* Michael De Vlieger, Dec 30 2016 *)

Formula

a(n) = Product_{i=1..n} A280246(i).