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A253975
a(n) is the smallest number k representable as x*y+x+y, where x>=y>1, in exactly n ways, or -1 if no such k exists.
2
8, 23, 35, 59, 191, 119, 179, 239, 575, 359, 1295, 899, 719, 839, 9215, 1259, 17324, 1679, 2879, 15359, 3599, 2519, 6479, 61439, 6299, 6719, 280664, 5039, 155924, 7559, 46079, 983039, 25919, 10079, 225224, 32399, 184319, 15119, 44099, 20159, 1403324, 107519, 25199
OFFSET
1,1
COMMENTS
a(45) = 8303765624.
Conjecture: no term is -1.
EXAMPLE
a(1) = 8 = 2*2+2+2.
a(2) = 23 = 5*3+5+3 = 7*2+7+2.
a(3) = 35 = 11*2+11+2 = 8*3+8+3 = 5*5+5+5.
CROSSREFS
Sequence in context: A283848 A341770 A287167 * A003342 A345833 A164284
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Jan 24 2015
STATUS
approved