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.

A369185 Numbers k such that Omega(k) = 1 + Omega(k+1) = 2 + Omega(k+2).

Original entry on oeis.org

45, 104, 105, 165, 260, 261, 344, 345, 357, 440, 465, 476, 477, 561, 776, 860, 861, 884, 885, 981, 1016, 1017, 1112, 1160, 1185, 1269, 1281, 1395, 1424, 1544, 1572, 1624, 1644, 1652, 1683, 1808, 1812, 1827, 1905, 1917, 1989, 2037, 2060, 2061, 2097, 2145, 2277, 2444, 2445, 2805, 2817, 2852, 2877
Offset: 1

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Author

Zak Seidov and Robert Israel, Jan 15 2024

Keywords

Comments

Numbers k such that both k and k+1 are in A369139.

Examples

			a(4) = 165 is a term because 165 = 3 * 5 * 11 has 3 prime factors (counted with multiplicity), 166 = 2 * 83 has 2 and 167 (which is prime) has 1.
		

Crossrefs

Cf. A001222, A369139. Includes x-2 for x in A201147.

Programs

  • Maple
    N:= 10^4: # for terms <= N
    V:= map(numtheory:-bigomega, [$1..N+2]):
    select(t -> V[t] = 1 + V[t+1] and V[t] = 2 + V[t+2], [$1..N]);