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A141089 Integral quotients of products of consecutive composites divided by their sums: Last consecutive composite. 5
4, 9, 14, 18, 22, 25, 26, 33, 48, 49, 78, 80, 84, 95, 105, 110, 114, 115, 119, 123, 124, 129, 147, 150, 152, 158, 160, 170, 175, 184, 190, 200, 202, 212, 213, 242, 245, 250, 256, 258, 272, 284, 287, 288, 291, 306, 309, 314, 319, 327, 332, 333, 336, 342, 343 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

Find the products and sums of consecutive composites. When the products divided by the sums produce integral quotients, add terms to sequence.

EXAMPLE

a(3) = 14 because 4*6*8*9*10*12*14 = 2903040 and 4+6+8+9+10+12+14 = 63; 2903040/63 = 46080, integral -- 14 is added to the sequence.

MATHEMATICA

comp = Select[Range[500], CompositeQ]; comp[[Position[Rest @ FoldList[Times, 1, comp]/Accumulate[comp], _?IntegerQ] // Flatten]] (* Amiram Eldar, Jan 12 2020 *)

CROSSREFS

Cf. A141090, A141091, A141092.

Compare with A140761, A159578, A140763, A116536.

Sequence in context: A313020 A313021 A313022 * A313023 A313024 A313025

Adjacent sequences:  A141086 A141087 A141088 * A141090 A141091 A141092

KEYWORD

easy,nonn

AUTHOR

Enoch Haga, Jun 01 2008

STATUS

approved

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Last modified November 24 18:11 EST 2020. Contains 338616 sequences. (Running on oeis4.)