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A239685
Prime numbers for which the sum of reciprocals of nonzero digits equals 1.
0
263, 2063, 4463, 4643, 6203, 20063, 26003, 60443, 62003, 64403, 68483, 69929, 86843, 88463, 88643, 92699, 200063, 260003, 260999, 296099, 296909, 400643, 406403, 406883, 446003, 449699, 460403, 464003, 464999, 468803, 488603, 494699, 496499, 496949, 499649
OFFSET
1,1
COMMENTS
Primes in A214959.
Property of the sequence: a(n) == 3 or 9 (mod 10). If n contains nonzero digits, each number > 263 contains at least two identical digits, and the subsequence of the corresponding sum of reciprocals of digits (primes in A037268) is finite.
EXAMPLE
2063 is in the sequence because 1/2 + 1/6 + 1/3 = 1.
MAPLE
with(numtheory):nn:=500000:for m from 1 to nn do:n:=ithprime(m):y:=convert(n, base, 10):n2:=nops(y):s:=0:for i from 1 to n2 do: if y[i]<>0 then s:=s+1/y[i]:else fi:od:if s=1 then printf(`%d, `, n):else fi:od:
MATHEMATICA
Select[Prime[Range[42000]], Total[1/Select[IntegerDigits[#], #!=0&]]==1&] (* Harvey P. Dale, May 31 2019 *)
CROSSREFS
Sequence in context: A023314 A054802 A369877 * A108823 A229480 A266036
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Mar 24 2014
STATUS
approved