A301416 Numbers k in A301413 such that k * A002110 (m) is in A002201.

1, 2, 4, 12, 24, 48, 144, 720, 1440, 10080, 30240, 60480, 302400, 604800, 6652800, 19958400, 259459200, 518918400, 3632428800, 61751289600, 185253868800, 926269344000, 17599117536000, 35198235072000, 809559406656000, 1619118813312000, 4857356439936000

Offset

1,2

Links

Michael De Vlieger, Table of n, a(n) for n = 1..170

Michael De Vlieger, Plot m = a(x) * A002110(y) at (x,y) for m in A002201, smallest 4096 terms m.

Example

From Michael De Vlieger, May 14 2018: (Start)
Numbers m = A301416(x) * A002110(y) that are in A002201 are plotted below.
      1     2     3     4      5        6        7 ...
  +-----------------------------------------------
1 |   2
2 |   6    12
3 |        60   120   360
4 |                  2520   5040
5 |                        55440
6 |                       720720  1441440  4324320
...
(End)

Mathematica

t = Import["b002201.txt", "Data"][[All, -1]]; (* Uses b-file at A002201 Alternatively, use this conversion of terms at A000705 to a 10^4 term dataset for A002201. Processing 10^4 terms will take a long time: *) t = With[{s = Import["b000705.txt", "Data"][[All, -1]]}, FoldList[Times, s]]; f[n_] := With[{d = FactorInteger@ n}, If[n == 1, {0}, ReplacePart[Table[0, {PrimePi[d[[-1, 1]]]}], #] &@ Map[PrimePi@ First@ # -> Last@ # &, d]]]; Union@ Array[Times @@ MapIndexed[Prime[First@#2]^#1 &, #3] & @@ {#1, Boole[First@ #2 > 0] Length@ #2, DeleteCases[-1 + #2, 0] /. -1 -> 0} & @@ {t[[#]], f@ t[[#]]} &, Length@ t]

Crossrefs

Cf. A002110, A002201, A301413, A301414.

Sequence in context: A291779 A181809 A181806 * A340137 A348092 A343458

Adjacent sequences: A301413 A301414 A301415 * A301417 A301418 A301419

Keyword

nonn

Author

Michael De Vlieger, Apr 09 2018

Status

approved