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Numbers k such that k, k+1, k+2, k+3 are all of the form p*q^2 for distinct primes p,q.
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%I #21 Jul 22 2021 02:08:13

%S 17042641441,180383003522,231242161921,313187053922,349881182161,

%T 717767333521,740230547281,907336510801,1080505860722,1646310367681,

%U 1682581387922,1896109379522,2638936079522,2919248012401,3121595927522

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

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

%H Ray Chandler, <a href="/A308683/b308683.txt">Table of n, a(n) for n = 1..10000</a>

%H StackExchange, <a href="http://math.stackexchange.com/questions/64892/sequence-of-numbers-with-prime-factorization-pq2">Sequence of numbers with prime factorization pq^2</a>

%H <a href="/index/Pri#prime_signature">Index to sequences related to prime signature</a>

%e 17042641441 = 7 * 7 * 347809009,

%e 17042641442 = 2 * 92311 * 92311,

%e 17042641443 = 3 * 3 * 1893626827,

%e 17042641444 = 2 * 2 * 4260660361.

%Y Cf. A054753, A074172, A178032, A141621.

%K nonn

%O 1,1

%A _Ray Chandler_, Jun 21 2019