A067501 Powers of 4 with digit sum also a power of 4.

1, 4, 68719476736, 95780971304118053647396689196894323976171195136475136, 25108406941546723055343157692830665664409421777856138051584, 1606938044258990275541962092341162602522202993782792835301376

Offset

0,2

Comments

The next term (a(6)) has 915 digits. - Harvey P. Dale, Feb 12 2022

Links

Table of n, a(n) for n=0..5.

Mathematica

Select[4^Range[0, 100], IntegerQ[Log[4, Total[IntegerDigits[#]]]]&] (* Harvey P. Dale, Feb 12 2022 *)

Crossrefs

Cf. A067499, A067500.

Sequence in context: A067508 A034250 A058436 * A066545 A161405 A147876

Adjacent sequences: A067498 A067499 A067500 * A067502 A067503 A067504

Keyword

nonn,base

Author

Amarnath Murthy, Feb 11 2002

Extensions

More terms from Sascha Kurz, Mar 18 2002

Status

approved