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A358988
Oblong numbers which are products of four distinct primes.
0
210, 462, 870, 930, 1122, 1190, 1482, 1722, 1806, 3306, 4422, 4970, 6162, 7310, 7482, 8742, 8930, 10302, 10506, 11990, 12882, 14042, 15006, 17030, 17822, 18906, 19182, 20022, 20306, 21170, 25122, 30102, 31506, 32942, 36290, 40602, 41006, 42230, 45582, 46010, 47306
OFFSET
1,1
EXAMPLE
210 = 14*15 = 2*3*5*7.
1122 = 33*34 = 2*3*11*17.
10302 = 101*102 = 2*3*17*101.
20306 = 142*143 = 2*11*13*71.
MATHEMATICA
Select[(#*(# + 1)) & /@ Range[220], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1} &] (* Amiram Eldar, Dec 10 2022 *)
CROSSREFS
Intersection of A002378 and A046386.
Sequence in context: A360146 A147571 A306508 * A254466 A235304 A121479
KEYWORD
nonn
AUTHOR
Massimo Kofler, Dec 10 2022
STATUS
approved