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 A109383 #12 Oct 13 2019 09:42:06 %S A109383 112,120,162,300,304,378,392,396,408,520,552,567,592,612,630,656,675, %T A109383 680,688,696,700,750,780,918,924,944,952,980,990,1044,1100,1116,1136, %U A109383 1140,1160,1168,1170,1242,1264,1272,1300,1323,1352,1372,1380,1386,1416,1470 %N A109383 5-almost primes of the form semiprime + 1. %H A109383 Charles R Greathouse IV, <a href="/A109383/b109383.txt">Table of n, a(n) for n = 1..10000</a> %F A109383 a(n) is in this sequence iff a(n) is in A014614 and (a(n)-1) is in A001358. %e A109383 a(1) = 112 because (3*37)+1 = (2^4) * 7 = 112. %e A109383 a(2) = 120 because (7*17)+1 = (2^3) * 3 * 5 = 120. %e A109383 a(3) = 162 because (7*23)+1 = 2 * (3^4) = 162. %t A109383 f[n_] := Plus @@ Last /@ FactorInteger[n];Select[Range[1500], f[ # ] == 5 && f[ # - 1] == 2 &] (* _Ray Chandler_, Mar 20 2007 *) %o A109383 (PARI) v=vector(10000);i=0; for(n=1,9e99, if(issemi(n)&bigomega(n+1)==5, v[i++]=n+1;if(i==#v, return))); v \\ _Charles R Greathouse IV_, Feb 14 2011 %Y A109383 Primes are in A000040. Semiprimes are in A001358. 5-almost primes are in A014614. %Y A109383 Primes of the form semiprime + 1 are in A005385 (safe primes). %Y A109383 Semiprimes of the form semiprime + 1 are in A109373. %Y A109383 3-almost primes of the form semiprime + 1 are in A109067. %Y A109383 4-almost primes of the form semiprime + 1 are in A109287. %Y A109383 5-almost primes of the form semiprime + 1 are in this sequence. %Y A109383 Least n-almost prime of the form semiprime + 1 are in A128665. %Y A109383 Cf. A077065, A079148, A092307. %K A109383 easy,nonn %O A109383 1,1 %A A109383 _Jonathan Vos Post_, Aug 25 2005 %E A109383 Extended by _Ray Chandler_, Mar 20 2007