  Decayless kink oscillations, which are nearly omnipresent in the solar
corona, are believed to be driven by continuously operating energy supply. In
this letter, we investigate an external continuous excitation of an apparent
decayless oscillation during an X1.1 flare on June 20, 2023
(SOL2023-06-20T16:42).The decayless kink oscillation was identified in the
coronal loop at extreme ultraviolet (EUV) wavelengths and the associated flare
quasi-periodic pulsations (QPPs) were simultaneously observed in passbands of
hard X-ray (HXR), microwave, and ultraviolet (UV) emissions. The kink
oscillation is detected as a transverse oscillation of the coronal loop, which
reveals five apparent cycles with an average period of about 130-10 s. The
oscillation amplitude does not show any significantly decay, suggesting a
decayless oscillation. At the same time, the solar flare occurs in the vicinity
of the oscillating loop and exhibits five main pulses in HXR, microwave, and UV
emissions, which could be regarded as flare QPPs. They have similar periods of
about 100-130 s, which may indicate successive and repetitive energy releases
during the flare impulsive phase. The peak of each loop oscillation cycle
appears to follow the pulse of the QPPs, suggesting that the transverse
oscillation is closely associated with flare QPPs. Our observations support the
scenario where the repetitive energy released following flare QPPs could be
invoked as external, continuously operating drivers of the apparent decayless
kink oscillation.
