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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. 4
17042641441, 180383003522, 231242161921, 313187053922, 349881182161, 717767333521, 740230547281, 907336510801, 1080505860722, 1646310367681, 1682581387922, 1896109379522, 2638936079522, 2919248012401, 3121595927522 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

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

EXAMPLE

17042641441 = 7 * 7 * 347809009,

17042641442 = 2 * 92311 * 92311,

17042641443 = 3 * 3 * 1893626827,

17042641444 = 2 * 2 * 4260660361.

CROSSREFS

Cf. A054753, A074172, A178032, A141621.

Sequence in context: A186176 A233805 A227894 * A101815 A113643 A233799

Adjacent sequences:  A308680 A308681 A308682 * A308684 A308685 A308686

KEYWORD

nonn

AUTHOR

Ray Chandler, Jun 21 2019

STATUS

approved

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Last modified May 26 20:51 EDT 2022. Contains 354092 sequences. (Running on oeis4.)