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 A115403 #14 Aug 11 2024 07:13:14 %S A115403 3,9,10,12,13,21,25,30,34,36,40,46,52,66,76,81,90,96,118,120,126,130, %T A115403 132,142,144,154,165,168,172,177,180,193,196,198,204,216,226,228,238, %U A115403 240,246,250,256,262,268,273,282,288,294,312,333,336,345,346,366,370 %N A115403 Numbers k such that k^3+1 is 3-almost prime (product of three primes). %C A115403 It appears that there is only one known example of three consecutive primes p, q, r whose product is 1 more than a perfect cube, namely 7*11*13 = 1001 and that probably no other examples exist. - _N. J. A. Sloane_, Apr 27 2008 %H A115403 Charles R Greathouse IV, <a href="/A115403/b115403.txt">Table of n, a(n) for n = 1..10000</a> %F A115403 k^3+1=p*q*r where p, q, r are primes (not necessarily distinct). %e A115403 9 is a member because 9^3+1=730=2*5*73 (product of three primes). %t A115403 Select[Range[370],PrimeOmega[#^3+1]==3&] (* _James C. McMahon_, Aug 10 2024 *) %o A115403 (PARI) isok(n) = bigomega(n^3+1) == 3; \\ _Michel Marcus_, Oct 10 2013 %Y A115403 Cf. A001093, A014612 (3-almost primes). %K A115403 nonn %O A115403 1,1 %A A115403 _Zak Seidov_, Mar 08 2006