A097620 Numbers having more prime factors than their neighbors together.

12, 16, 18, 24, 30, 32, 36, 40, 42, 48, 54, 60, 64, 72, 84, 88, 90, 96, 102, 108, 112, 120, 128, 132, 138, 140, 144, 150, 156, 160, 162, 168, 180, 192, 198, 200, 210, 216, 224, 228, 234, 240, 250, 252, 256, 264, 270, 272, 280, 282, 288, 294, 300, 304, 306, 308

Offset: 1

Author

Reinhard Zumkeller, Aug 17 2004

Keywords

• nonn

Examples

			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.
		

Links

• Michael S. Branicky, Table of n, a(n) for n = 1..10000

Crossrefs

Subsequence of A097619.

Cf. A001222.

Programs

Python

from sympy import primeomega
def ok(n): return primeomega(n) > primeomega(n-1) + primeomega(n+1)
print([k for k in range(2, 309) if ok(k)]) # Michael S. Branicky, Dec 16 2021

Formula

{k: A001222(k) > A001222(k-1) + A001222(k+1)}. - Michael S. Branicky, Dec 16 2021