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We report an improved absolute frequency measurement of the 5s2 1S0 -5s5p 3P0 narrowline clock transition at 236.5 nm, for a single trapped and laser cooled 115In+. Using a narrowline laser as the local oscillator, a linewidth of 43 Hz for the transition is resolved. For absolute frequency measurement we use an optical frequency comb referenced to a cesium clock The transition frequency is found to be 1, 267, 402, 452, 900, 967 (63) Hz, averaged over 13 days of separate measurements. The accuracy is about 5.0 times 10-14 . And a preliminary absolute frequency measurement is shown with a Hydrogen maser as the reference. We discuss possibilities for further improvement.