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A033637 Products of partition numbers A000041(n). 3
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 27, 28, 30, 32, 33, 35, 36, 40, 42, 44, 45, 48, 49, 50, 54, 55, 56, 60, 63, 64, 66, 70, 72, 75, 77, 80, 81, 84, 88, 90, 96, 98, 99, 100, 101, 105, 108, 110, 112, 120, 121, 125, 126, 128, 132, 135, 140 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Range of A000688.

LINKS

David W. Wilson, Table of n, a(n) for n = 1..10000

MAPLE

with(combinat): A000041:=proc(n) options remember: RETURN(numbpart(n)): end: partdiv:=proc(m, i) local j, q, f: f:=0: for j from i by -1 to 2 while(f=0) do if(irem(m, A000041(j))=0) then q:=iquo(m, A000041(j)): if(q=1) then RETURN(1) else f:=partdiv(q, j) fi fi od: RETURN(f): end: for i from 2 to 15 do for n from A000041(i) to A000041(i+1)-1 do m:=partdiv(n, i): if m=1 then printf("%d, ", n) fi od od: (C. Ronaldo)

MATHEMATICA

p0 = Table[ PartitionsP[n], {n, 1, 40 (* ~ 1148 terms *)}] ; f[p_] := Select[ Outer[Times, p, p] // Flatten // Union, # <= Last[p0] &]; FixedPoint[f, p0] (* Jean-Fran├žois Alcover, Oct 03 2013 *)

PROG

(PARI) is(n, mx=n)=if(n>>valuation(n, 2)==1, return(1)); for(i=3, n, my(p=numbpart(i), m=n); while(m%p==0, if(is(m/=p), return(1))); if(p>n, return(0))) \\ Charles R Greathouse IV, Jun 28 2013

CROSSREFS

Cf. A046064.

Sequence in context: A194424 A033892 A033620 * A084347 A051038 A140332

Adjacent sequences:  A033634 A033635 A033636 * A033638 A033639 A033640

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 02 2005

STATUS

approved

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Last modified May 22 13:33 EDT 2017. Contains 286872 sequences.