OFFSET
1,4
LINKS
Indranil Ghosh, Table of n, a(n) for n = 1..505
FORMULA
a(1) = 1; for n>1, a(n) = Product_{i=2..n} A051953(i).
MATHEMATICA
Table[If[n==1, 1, Product[i - EulerPhi[i], {i, 2, n}]], {n, 1, 29}] (* Indranil Ghosh, Mar 09 2017 *)
PROG
(Magma) [1] cat [&*[#[h: h in [2..k] | GCD(h, k) ne 1]: k in [2..n]]: n in [2..100]]
(PARI) for (n=1, 29, print1(if(n==1, 1, prod(i=2, n, i - eulerphi(i))), ", ")); \\ Indranil Ghosh, Mar 09 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Jan 13 2017
STATUS
approved