A308683 Numbers k such that k, k+1, k+2, k+3 are all of the form p*q^2 for distinct primes p,q.

17042641441, 180383003522, 231242161921, 313187053922, 349881182161, 717767333521, 740230547281, 907336510801, 1080505860722, 1646310367681, 1682581387922, 1896109379522, 2638936079522, 2919248012401, 3121595927522

Offset: 1

Author

Ray Chandler, Jun 21 2019

Keywords

• nonn

Comments

See StackExchange link for pseudo-code to generate four or five consecutive values of the form.

Examples

			17042641441 = 7 * 7 * 347809009,
17042641442 = 2 * 92311 * 92311,
17042641443 = 3 * 3 * 1893626827,
17042641444 = 2 * 2 * 4260660361.
		

Links

• Ray Chandler, Table of n, a(n) for n = 1..10000
• StackExchange, Sequence of numbers with prime factorization pq^2
• Index to sequences related to prime signature

Crossrefs

Cf. A054753, A074172, A178032, A141621.