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A359230
a(n) is the index of the smallest square pyramidal number with exactly n distinct prime factors.
1
1, 2, 3, 4, 17, 27, 76, 220, 747, 2232, 5719, 18980, 159340, 437580, 1672307, 10891075, 78604064
OFFSET
0,2
LINKS
Eric Weisstein's World of Mathematics, Distinct Prime Factors
Eric Weisstein's World of Mathematics, Square Pyramidal Number
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Ilya Gutkovskiy, Dec 22 2022
EXTENSIONS
a(16) from Jon E. Schoenfield, Dec 22 2022
STATUS
approved