cp's OEIS Frontend

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.

A097620 Numbers having more prime factors than their neighbors together.

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%I A097620 #10 Dec 16 2021 10:38:57
%S A097620 12,16,18,24,30,32,36,40,42,48,54,60,64,72,84,88,90,96,102,108,112,
%T A097620 120,128,132,138,140,144,150,156,160,162,168,180,192,198,200,210,216,
%U A097620 224,228,234,240,250,252,256,264,270,272,280,282,288,294,300,304,306,308
%N A097620 Numbers having more prime factors than their neighbors together.
%H A097620 Michael S. Branicky, <a href="/A097620/b097620.txt">Table of n, a(n) for n = 1..10000</a>
%F A097620 {k: A001222(k) > A001222(k-1) + A001222(k+1)}. - _Michael S. Branicky_, Dec 16 2021
%e A097620 A001222(64) = A001222(2^6) = 6, A001222(64-1) = A001222(3*3*7) = 3, A001222(64+1) = A001222(5*13) = 2, and 6 > 3+2, therefore 64 is a term.
%o A097620 (Python)
%o A097620 from sympy import primeomega
%o A097620 def ok(n): return primeomega(n) > primeomega(n-1) + primeomega(n+1)
%o A097620 print([k for k in range(2, 309) if ok(k)]) # _Michael S. Branicky_, Dec 16 2021
%Y A097620 Subsequence of A097619.
%Y A097620 Cf. A001222.
%K A097620 nonn
%O A097620 1,1
%A A097620 _Reinhard Zumkeller_, Aug 17 2004