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A373084
Numbers k such that the sums of digits of k and 1/k in factorial base (A007623) are equal.
0
1, 2, 3, 6, 12, 15, 24, 45, 70, 105, 120, 576, 700, 720, 1008, 1152, 4800, 5040, 5670, 8960, 14175, 17820, 18711, 24640, 25920, 28800, 32256, 33264, 36960, 39312, 39936, 40320, 64800, 69498, 88452, 89600, 90720, 98560, 118272, 120960, 138996, 147840, 164736, 193536
OFFSET
1,2
COMMENTS
Numbers k such that A034968(k) = A276350(k).
All the factorials (A000142) are terms, since A034968(k!) = A276350(k!) = 1 for k >= 0.
EXAMPLE
The first 6 terms are:
n a(n) a(n) in factorial base 1/a(n) in factorial base sum of digits
- ---- ---------------------- ------------------------ -------------
1 1 1 1 1
2 2 10 0.01 1
3 3 11 0.002 2
4 6 100 0.001 1
5 12 200 0.0002 2
6 15 211 0.00013 4
MATHEMATICA
Select[Range[1000], Total@ NumberDecompose[#, Reverse@Range[#]!] == Total@ NumberDecompose[1/#, 1/Range[#]!] &]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, May 23 2024
STATUS
approved