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A080374 a(n)=lcm of first n consecutive prime differences. 6
1, 2, 2, 4, 4, 4, 4, 4, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 24, 24, 24, 24, 24, 24, 168, 168, 168, 168, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840, 840 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Michael De Vlieger, Table of n, a(n) for n = 1..10000

EXAMPLE

n=25: first 25 distinct differences are {1,2,4,6,8}, lcm=24=a(25)

From Michael De Vlieger, May 12 2017: (Start)

Record values of a(n) set at A080376(n):

    n  A080376(n)  a(A080376(n))

    1        2     1

    2        4     2

    3        9     4

    4       24     12

    5       30     24

    6       34     168

    7       99     840

    8      189     2520

    9      217     27720

   10      282     471240

   11      367     942480

   12      738     12252240

   13     3302     24504480

   14     3427     465585120

   15     3644     2327925600

   16     3793     72165693600

   17     4612     216497080800

   18     7970     6278415343200

   19     8688     144403552893600

   20    14357     288807105787200

   21    23283     12418705548849600

   22    34202     509166927502833600

   23    49414     18839176317604843200

   24    85633     131874234223233902400

   25    85787     6989334413831396827200

  ...

(End)

MATHEMATICA

tb[x_] := Table[Prime[w+1]-Prime[w], {w, 1, x}] Table[Apply[LCM, tb[j]], {j, 1, 256}]

(* Second program: *)

FoldList[LCM @@ {#1, #2} &, Differences@ Array[Prime, 61]] (* Michael De Vlieger, May 12 2017 *)

PROG

(PARI) lista(nn) = {my(v = primes(nn)); my(vd = vector(nn-1, i, v[i+1] - v[i])); for (i=1, nn-1, print1(lcm(vector(i, k, vd[k])), ", "); ); } \\ Michel Marcus, May 13 2017

CROSSREFS

Cf. A001223, A080375.

Sequence in context: A156726 A082852 A083551 * A165040 A035683 A261009

Adjacent sequences:  A080371 A080372 A080373 * A080375 A080376 A080377

KEYWORD

nonn

AUTHOR

Labos Elemer, Feb 27 2003

STATUS

approved

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Last modified August 12 00:34 EDT 2022. Contains 356067 sequences. (Running on oeis4.)