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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A351096 Semiprimes that are the arithmetic derivative (A003415) of some number.

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%I A351096 #6 Feb 03 2022 16:45:20
%S A351096 4,6,9,10,14,15,21,22,25,26,33,34,38,39,46,49,51,55,58,62,69,74,77,82,
%T A351096 85,86,87,91,94,95,106,111,115,118,119,121,122,123,129,133,134,141,
%U A351096 142,143,146,155,158,159,161,166,169,178,183,185,187,194,201,202,203,206,213,214,215,218,221,226,235,247,249,253
%N A351096 Semiprimes that are the arithmetic derivative (A003415) of some number.
%o A351096 (PARI)
%o A351096 A002620(n) = ((n^2)>>2);
%o A351096 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A351096 isA351096(n) = if(2!=bigomega(n), 0, for(k=1,A002620(n),if(A003415(k)==n,return(1))); (0));
%Y A351096 Complement of A351095 in A001358. Subsequence of A239433.
%Y A351096 Cf. A003415, A189441.
%K A351096 nonn
%O A351096 1,1
%A A351096 _Antti Karttunen_, Feb 03 2022