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.
%I A362410 #15 May 06 2024 22:59:49 %S A362410 19,33,45,51,59,61,65,67,69,77,85,93,105,109,113,129,141,165,181,193, %T A362410 197,201,211,213,217,221,227,237,257,261,267,277,291,301,309,317,345, %U A362410 347,353,357,365,393,397,401,409,417,421,437,445,461,465,477,497,521,561,569,597,613,633,653,661,677 %N A362410 Numbers k such that A000292(k) is in A046386. %C A362410 Numbers k such that k*(k+1)*(k+2)/6 is the product of four distinct primes. %C A362410 All terms are odd. %H A362410 Robert Israel, <a href="/A362410/b362410.txt">Table of n, a(n) for n = 1..10000</a> %F A362410 A000292(a(n)) = A353027(n). %e A362410 a(3) = 45 is a term because 45*46*47/6 = 16215 = 3*5*23*47 is the product of four distinct primes. %p A362410 filter:= k -> ifactors(k*(k+1)*(k+2)/6)[2][..,2] = [1,1,1,1]; %p A362410 select(filter, [seq(i,i=1..1000,2)]); %t A362410 p4dpQ[n_]:=With[{c=(n(n+1)(n+2))/6},PrimeNu[c]==PrimeOmega[c]==4]; Select[Range[ 700],p4dpQ] (* _Harvey P. Dale_, May 06 2024 *) %o A362410 (PARI) isok(k) = my(t=k*(k+1)*(k+2)/6); (omega(t)==4) && (bigomega(t)==4); \\ _Michel Marcus_, Apr 20 2023 %Y A362410 Cf. A000292, A046386, A353027. %K A362410 nonn %O A362410 1,1 %A A362410 _Robert Israel_, Apr 18 2023