A364436 Numbers that begin a run of at least 4 consecutive integers having exactly 6 distinct prime factors each (i.e., belonging to A074969).

7933641735, 9338016258, 9827010633, 10744118592, 10808993635, 10928652579, 13302330390, 15300915705, 16088310249, 16408242849, 18685633314, 18721086153, 19136152098, 19819102092, 20592248544, 20826707802, 21241193334, 21296349633, 21531380583, 21727956885, 21823418253

Offset

1,1

Links

Table of n, a(n) for n=1..21.

Example

7933641735 is in the sequence as it starts a run of at least 4 consecutive integers each of which has exactly 6 distinct prime factors.
That is, each of 7933641735 = 3 * 5 * 23 * 83 * 461 * 601,
7933641735 + 1 = 7933641736 = 2^3 * 17 * 47 * 59 * 109 * 193,
7933641735 + 2 = 7933641737 = 7 * 29 * 31 * 41 * 97 * 317,
7933641735 + 3 = 2 * 3 * 11 * 89 * 563 * 2399 has 6 distinct prime factors.

Prog

(PARI) upto(n) = {my(res = List(), streak = 0); n+=3; forfactored(i = 1, n, if(omega(i[2]) == 6, streak++; if(streak >= 4, listput(res, i[1]-3)), streak = 0)); res}

Crossrefs

Cf. A074969, A364265.

Sequence in context: A015413 A288090 A306828 * A075131 A250865 A108880

Adjacent sequences: A364433 A364434 A364435 * A364437 A364438 A364439

Keyword

nonn

Author

David A. Corneth, Jul 24 2023

Extensions

More terms from Jinyuan Wang, Aug 12 2023

Status

approved