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A207852
Smallest number m such that there are exactly n ways to partition the numbers {1,...,m} into nonempty sets P and S with the product of the elements of P equal to the sum of elements in S.
3
1, 3, 12, 10, 19, 26, 33, 39, 55, 74, 48, 62, 71, 99, 45, 140, 96, 176, 104, 144, 159, 175, 230, 191, 320, 328, 240, 334, 259, 344, 279, 308, 303, 505, 419, 560, 714, 550, 455, 665, 684, 670, 751, 935, 899, 800, 1051, 776, 928, 602, 749, 1104, 689, 1295, 1364
OFFSET
0,2
COMMENTS
A178830(a(n)) = n and A178830(m) <> n for m < a(n).
EXAMPLE
a(1) = 3: 3 = 1+2;
a(2) = 12: 1*5*12 = 2+3+4+6+7+8+9+10+11, 2*4*8 = 1+3+5+6+7+9+10+11+12;
a(3) = 10: 1*2*3*7 = 4+5+6+8+9+10, 1*4*10 = 2+3+5+6+7+8+9, 6*7 = 1+2+3+4+5+8+9+10.
PROG
(Haskell)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a207852 n = (fromJust $ elemIndex n a178830_list) + 1
CROSSREFS
Sequence in context: A018876 A038230 A292581 * A182455 A110345 A018999
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Feb 21 2012
EXTENSIONS
a(25)-a(54) from Alois P. Heinz, Jun 07 2012
STATUS
approved