A348882 Numbers that are expressible as the product of the number of distinct prime factors of preceding integers.

16, 48, 72, 96, 144, 432, 576, 1296, 2592, 5184, 20736, 32805, 221184, 1555200, 11197440, 55987200, 95551488, 268738560, 302330880, 382205952, 524880000, 671846400, 6718464000, 34012224000, 155520000000, 403107840000, 6856864358400, 107495424000000, 110075314176000

Offset: 1

Author

Metin Sariyar, Nov 02 2021

Keywords

• nonn

Examples

			The number of distinct prime factors of the numbers 15, 14, 13, 12, 11, 10 are respectively 2, 2, 1, 2, 1, 2 and 2*2*1*2*1*2 = 16, hence 16 is a term.
		

Crossrefs

Cf. A001221, A000961, A007774, A033992, A033993, A051270, A074969, A176655, A348266.

Programs

Mathematica

om[n_] := om[n] = PrimeNu[n]; q[n_] := Module[{m = n, k = n - 1}, While[k > 1 && Divisible[m, om[k]], m /= om[k]; k--]; m == 1]; Select[Range[2, 10^6], q] (* Amiram Eldar, Nov 02 2021 *)

Extensions

a(13)-a(17) from Amiram Eldar, Nov 02 2021

More terms from David A. Corneth, Nov 02 2021