|
Search: id:A069025
|
|
|
| A069025 |
|
Smallest power of 2 with digital sum (A007953) n, or 0 if no such number exists. |
|
+0
2
|
|
| 1, 2, 0, 4, 32, 0, 16, 8, 0, 64, 128, 0, 256, 2048, 0, 0, 0, 0, 4096, 8192, 0, 16384, 0, 0, 65536, 32768, 0, 0, 524288, 0, 1048576, 0, 0, 0, 134217728, 0, 16777216, 0, 0, 67108864, 8388608, 0, 268435456, 0, 0, 4398046511104, 2147483648, 0, 0
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
a(3k)=0. In general about half the entries are nonzero.
|
|
EXAMPLE
|
Both 2^4=16 and 2^10=1024 have a digital sum of 7 but 2^4 is the smaller so it is the one presented.
|
|
MATHEMATICA
|
a = Table[0, {50}]; Do[b = Plus @@ IntegerDigits[2^n]; If[b < 51 && a[[b]] == 0, a[[b]] = 2^n], {n, 0, 10^4}]; a
|
|
CROSSREFS
|
Cf. A007632.
Adjacent sequences: A069022 A069023 A069024 this_sequence A069026 A069027 A069028
Sequence in context: A002938 A111938 A055978 this_sequence A066442 A086134 A071090
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Apr 02 2002
|
|
EXTENSIONS
|
Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 05 2002
|
|
|
Search completed in 0.002 seconds
|
