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A121853
Cumulative product of A000120.
0
1, 1, 1, 2, 2, 4, 8, 24, 24, 48, 96, 288, 576, 1728, 5184, 20736, 20736, 41472, 82944, 248832, 497664, 1492992, 4478976, 17915904, 35831808, 107495424, 322486272, 1289945088, 3869835264, 15479341056, 61917364224, 309586821120
OFFSET
0,4
COMMENTS
This sequence does not always have prime exponents decreasing (i.e., is not always a product of primorial numbers). The first exception is a(5932), which is divisible by 7^1214, but only 5^1213.
FORMULA
a(n) = Product_{k=1}^n A000120(k).
MATHEMATICA
Join[{1}, FoldList[Times, Table[DigitCount[n, 2, 1], {n, 40}]]] (* Harvey P. Dale, Dec 08 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved