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Compound filter: a(n) = P(A101296(n), A291751(n)), where P(n,k) is sequence A000027 used as a pairing function.
5

%I #14 Oct 09 2017 00:05:35

%S 1,5,8,18,17,40,30,71,58,82,23,126,80,124,124,197,57,196,138,237,214,

%T 235,93,359,256,304,356,412,327,570,173,640,469,500,469,791,498,599,

%U 634,828,255,912,668,867,909,410,408,1237,864,1041,410,1087,437,1233,410,1283,1132,1180,530,1724,1178,707,1437,1967,1435,1779,1433,1717,707,1779,353,2361

%N Compound filter: a(n) = P(A101296(n), A291751(n)), where P(n,k) is sequence A000027 used as a pairing function.

%C This filter combines information about A101296(n) (prime signature of n, A046523), A003557(n) and A048250(n). - _Antti Karttunen_, Oct 08 2017

%H Antti Karttunen, <a href="/A291752/b291752.txt">Table of n, a(n) for n = 1..16385</a>

%F a(n) = (1/2)*(2 + ((A101296(n) + A291751(n))^2) - A101296(n) - 3*A291751(n)).

%o (Scheme) (define (A291752 n) (* (/ 1 2) (+ (expt (+ (A101296 n) (A291751 n)) 2) (- (A101296 n)) (- (* 3 (A291751 n))) 2)))

%Y Cf. A000027, A003557, A046523, A048250, A101296, A291750, A291751.

%K nonn

%O 1,2

%A _Antti Karttunen_, Sep 06 2017

%E Formula corrected by _Antti Karttunen_, Oct 08 2017