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%I #10 Aug 10 2018 09:16:31
%S 0,1,2,4,7,10,14,19,25,32,40,49,59,70,82,95,110,125,141,159,178,197,
%T 219,242,265,290,315,341,370,400,432,464,498,534,570,608,647,688,730,
%U 773,818,863,910,957,1007,1060,1114,1168,1224,1281,1338,1398
%N [ (4th elementary symmetric function of P(n))/(3rd elementary symmetric function of P(n)) ], where P(n) = {1, p(1), p(2), ..., p(n-1)}, p(0) = 1.
%C p(i) denotes the i-th prime and [...] the floor function. - _M. F. Hasler_, Dec 11 2007
%F a(n) = floor(A024524(n)/A024523(n))
%o (PARI) /* symmetric polynomial of order n in X=[X1,...,XN] */ sympol(X,n,s)=forvec(i=vector(n,j,[1,#X]),s+=prod(k=1,n,X[i[k]]),2);s /* list of primes 0...n-1 with p(0)=1 */ P(n)=concat([1],vector(n-1,i,prime(i))) /* this sequence */ A024536(n) = sympol(P(n),4) \ sympol(P(n),3) \\ _M. F. Hasler_, Dec 11 2007
%Y Cf. A024523, A024524.
%K nonn
%O 4,3
%A _Clark Kimberling_
%E Extended (up to a(55)) by _M. F. Hasler_, Dec 11 2007
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