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A067501
Powers of 4 with digit sum also a power of 4.
10
1, 4, 68719476736, 95780971304118053647396689196894323976171195136475136, 25108406941546723055343157692830665664409421777856138051584, 1606938044258990275541962092341162602522202993782792835301376
OFFSET
1,2
COMMENTS
The next term (a(7)) has 915 digits. - Harvey P. Dale, Feb 12 2022
MATHEMATICA
Select[4^Range[0, 100], IntegerQ[Log[4, Total[IntegerDigits[#]]]]&] (* Harvey P. Dale, Feb 12 2022 *)
CROSSREFS
Sequence in context: A067508 A034250 A058436 * A066545 A161405 A147876
KEYWORD
nonn,base
AUTHOR
Amarnath Murthy, Feb 11 2002
EXTENSIONS
More terms from Sascha Kurz, Mar 18 2002
Offset changed by Andrew Howroyd, Sep 17 2024
STATUS
approved