login
(n-1)-st elementary symmetric function of the first n odd primes; a(0) = 0.
4

%I #23 Feb 06 2024 19:31:28

%S 0,1,8,71,886,12673,230456,4633919,111429982,3343015913,106868339918,

%T 4054408822031,169941130770676,7459593754902673,357142287146260646,

%U 19235986110046059943,1151217759731312559002,71185663518687172418657

%N (n-1)-st elementary symmetric function of the first n odd primes; a(0) = 0.

%C Arithmetic derivative of the product of first n odd primes. - _Antti Karttunen_, Jan 31 2024

%C Primes occur at indices: 3, 19, 23, 117, 119, 127, 161, 209, ..., and they are: 71, 346723099672193960193396979, 15360643606799479140185671512081451, ... - _Antti Karttunen_, Feb 06 2024

%H Antti Karttunen, <a href="/A203008/b203008.txt">Table of n, a(n) for n = 0..349</a>

%F From _Antti Karttunen_, Jan 31 2024 and Feb 06 2024: (Start)

%F a(n) = A003415(A070826(1+n)) = (1/2)*(A024451(1+n)-A070826(1+n)).

%F For n >= 1, a(n) = A327860(A060389(n)).

%F A000035(a(n)) = A000035(n).

%F (End)

%t f[k_] := Prime[k + 1]; t[n_] := Table[f[k], {k, 1, n}]

%t a[n_] := SymmetricPolynomial[n - 1, t[n]]

%t Table[a[n], {n, 1, 16}] (* A203008 *)

%o (PARI)

%o A002110(n) = prod(i=1,n,prime(i));

%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

%o A203008(n) = if(!n,n,A003415(A002110(1+n)/2)); \\ _Antti Karttunen_, Jan 31 2024

%Y Cf. A000035, A003415, A024451, A060389, A070826 (n-th. symm. function), A071148 (1st symm. func), A327860.

%K nonn

%O 0,3

%A _Clark Kimberling_, Dec 29 2011

%E Term a(0) = 0 prepended by _Antti Karttunen_, Jan 31 2024