(1) under section 6420 (determined without regard to ),
(2) under section 6421 (determined without regard to ), and
(3) under section 6427 (determined without regard to ).
Credit shall not be allowed under subsection (a) for any amount payable under section 6421 or 6427, if a claim for such amount is timely filed and, under or 6427(k), is payable under such section.