

A098908


Sorted products of primes (2,3,5,7...) and factorials (1,2,6,24...).


1



2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 17, 18, 19, 22, 23, 26, 29, 30, 31, 34, 37, 38, 41, 42, 43, 46, 47, 48, 53, 58, 59, 61, 62, 66, 67, 71, 72, 73, 74, 78, 79, 82, 83, 86, 89, 94, 97, 101, 102, 103, 106, 107, 109, 113, 114, 118, 120, 122, 127, 131, 134, 137, 138, 139
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OFFSET

1,1


LINKS



EXAMPLE

In the set of products of primes and factorials 10 (= 5 times factorial 2) is the seventh largest number and therefore is the seventh member of the sequence.


MAPLE

N:= 1000: # to get all terms <= N
P:= select(isprime, [2, seq(i, i=3..N, 2)]):
F:= 1: v:= 1:
for n from 2 do
v:= v*n;
if v > N then break fi;
F:= F, v;
od:
F:= {F}:
sort(convert(select(`<=`, {seq(seq(p*f, f=F), p=P)}, N), list)); # Robert Israel, Aug 27 2018


MATHEMATICA

With[{upto=140}, Select[Union[Flatten[Table[p*f, {p, Prime[ Range[ PrimePi[ upto]]]}, {f, Range[10]!}]]], #<=upto&]] (* Harvey P. Dale, Jul 19 2019 *)


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



