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A178332
Numbers n such that d(1)^p + d(2)^p-1 +... + d(p)^1 is a power of 2, where d(i), i=1..p, are the digits of n.
0
1, 2, 4, 8, 10, 11, 13, 17, 20, 24, 57, 100, 101, 103, 107, 110, 112, 116, 123, 156, 200, 248, 305, 314, 321, 480, 503, 512, 1000, 1001, 1003, 1007, 1010, 1012, 1016, 1023, 1056, 1100, 1102, 1106, 1111, 1115, 1122, 1155, 1247, 1304, 1313, 1320, 1502, 1511, 2037, 2040, 2136, 2208, 2217, 2224, 2394, 3263, 3344
OFFSET
1,2
EXAMPLE
2394 is in the sequence because 2^4 + 3^3 + 9^2 + 4^1 = 128 = 2^7.
MAPLE
with(numtheory):for n from 1 to 4000 do:l:=length(n):n0:=n:s1:=0:s2:=0:for
m from 1 to l do:q:=n0:u:=irem(q, 10):v:=iquo(q, 10):n0:=v :s2:=s2+u^m:od:x:=evalf(log[2](s2)):if x=floor(x) then printf(`%d, `, n):else fi:od:
CROSSREFS
Sequence in context: A296691 A028836 A028838 * A265155 A070305 A174567
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Dec 21 2010
STATUS
approved