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A385232
Numbers that can be written as s^x + t^y, with 1 < s < t and {s,t} = {x,y}; that is, are of the form s^s + t^t or s^t + t^s.
14
17, 31, 32, 57, 100, 145, 177, 260, 283, 320, 368, 593, 945, 1124, 1649, 2169, 2530, 3129, 3152, 3381, 4240, 5392, 7073, 8361, 16580, 18785, 20412, 23401, 32993, 46660, 46683, 46912, 49781, 60049, 65792, 69632, 94932, 131361, 178478, 262468, 268705, 397585, 423393, 524649, 533169, 823547, 823570
OFFSET
1,1
LINKS
EXAMPLE
a(1) = 2^3 + 3^2 = 8 + 9 = 17.
a(2) = 2^2 + 3^3 = 4 + 27 = 31.
a(3) = 2^4 + 4^2 = 16 + 16 = 32.
a(4) = 2^5 + 5^2 = 32 + 25 = 57.
CROSSREFS
Cf. A000312, A001597, A385233 (three addends).
Union of A173054 and A385614.
Sequence in context: A124884 A052006 A002675 * A333855 A321217 A095748
KEYWORD
nonn,easy
AUTHOR
Alberto Zanoni, Jun 28 2025
STATUS
approved