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A253914
Numbers that can be represented as both a^x + x and b^y + b, for some a, b, x, y > 1.
3
6, 18, 20, 30, 66, 258, 260, 732, 1026, 3130, 4098, 4100, 16386, 19686, 46662, 65538, 65540, 65552, 262146, 531444, 823550, 1048578, 1048580, 4194306, 9765630, 14348910, 16777218, 16777220, 16777224, 67108866, 268435458, 268435460, 387420492, 387420498, 1073741826
OFFSET
1,1
COMMENTS
Intersection of A099225 and A253913.
Includes a^(a*b)+a = (a^b)^a+a for a,b > 1. - Robert Israel, Apr 28 2019
EXAMPLE
a(1) = 6 = 2^2 + 2, in this case a = b = x = y = 2.
a(2) = 18 = 2^4 + 2 = 4^2 + 2.
a(8) = 732 = 3^6 + 3 = 9^3 + 3.
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Jan 18 2015
STATUS
approved