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A359304
Oblong numbers which are products of five distinct primes.
1
4290, 4830, 6006, 11130, 12210, 13110, 16770, 23870, 27390, 33306, 34410, 34782, 37830, 44310, 49062, 56406, 60762, 64770, 66822, 70490, 71022, 74802, 82082, 84390, 95790, 101442, 103362, 104006, 109230, 119370, 125670, 127806, 133590, 137270, 148610, 151710, 158802
OFFSET
1,1
EXAMPLE
4290 = 65*66 = 2*3*5*11*13.
4830 = 69*70 = 2*3*5*7*23.
6006 = 77*78 = 2*3*7*11*13.
11130 = 105*106 = 2*3*5*7*53.
MATHEMATICA
Select[(#*(# + 1)) & /@ Range[400], FactorInteger[#][[;; , 2]] == {1, 1, 1, 1, 1} &] (* Amiram Eldar, Dec 25 2022 *)
PROG
(PARI) select(x->((omega(x)==5) && (bigomega(x)==5)), vector(500, k, k*(k+1))) \\ Michel Marcus, Dec 25 2022
CROSSREFS
Intersection of A002378 and A046387.
Sequence in context: A101619 A239255 A252555 * A233888 A204408 A204401
KEYWORD
nonn
AUTHOR
Massimo Kofler, Dec 25 2022
STATUS
approved