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A141270
(0, 1, 2, 3, 2^2, 5, 2*3, 7, 2^3, 3^2, 2*5, 11, 2^2*3, ...) transform in (0*1, 2*3, 2*2, 5*2, 3*7, 2*3, 3*2, 2*5, 11*2, 2*3, ...).
15
0, 6, 4, 10, 21, 6, 6, 10, 22, 6, 26, 21, 10, 68, 6, 38, 4, 15, 14, 253, 6, 15, 4, 39, 6, 14, 58, 15, 62, 15, 22, 85, 14, 6, 74, 38, 39, 6, 205, 6, 301, 4, 33, 10, 46, 94, 12, 14, 10, 6, 34, 26, 106, 9, 55, 6, 21, 38, 1711, 4, 15, 122, 93, 14, 12, 65, 6, 737, 4, 51, 46, 35, 142, 9
OFFSET
1,2
LINKS
MATHEMATICA
Map[Times @@ # &, Partition[Flatten[{0}~Join~Array[DeleteCases[Flatten@ FactorInteger[#], 1] &, 72] /. {} -> {1}], 2, 2]] (* Michael De Vlieger, Oct 20 2021 *)
CROSSREFS
Sequence in context: A257926 A116946 A357128 * A040032 A239394 A376614
KEYWORD
nonn,less
AUTHOR
EXTENSIONS
A 65 replaced with 85, a 54 with 74, etc. by R. J. Mathar, Feb 21 2009
STATUS
approved