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A069710
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Primes with arithmetic mean of digits = 1 (sum of digits = number of digits).
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14
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11, 1021, 1201, 2011, 3001, 10103, 10211, 10301, 11003, 12011, 12101, 13001, 20021, 20201, 21011, 21101, 30011, 1000033, 1000213, 1000231, 1000303, 1001023, 1001041, 1001311, 1001401, 1002121, 1003003, 1003111, 1003201, 1010131
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OFFSET
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1,1
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COMMENTS
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The sum of the digits of a prime > 3 cannot be a multiple of 3, hence no prime with 3*k digits can be here. - David Radcliffe, May 05 2015
Subsequence of primes of A061384. - Michel Marcus, May 05 2015
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LINKS
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David Radcliffe, Table of n, a(n) for n = 1..13376
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MAPLE
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F:= proc(d, s) option remember;
local t, r;
if d = 1 then
if s >= 1 and s <= 9 then {s}
else {}
fi
else
`union`(seq(map(t -> 10*t+r, procname(d-1, s-r)), r=0..min(s, 9)))
fi
end proc:
`union`(seq(select(isprime, F(i, i)), i = remove(d -> d mod 3 = 0, [$1..8]));
# if using Maple 11 or earlier, uncomment the next line
# sort(convert(%, list)); # Robert Israel, May 05 2015
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MATHEMATICA
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Do[p = Prime[n]; If[ Apply[ Plus, IntegerDigits[p]] == Floor[ Log[10, p] + 1], Print[p]], {n, 1, 10^5}]
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CROSSREFS
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Cf. A069709, A069711, A069712.
Sequence in context: A065050 A099440 A073903 * A046187 A234634 A004811
Adjacent sequences: A069707 A069708 A069709 * A069711 A069712 A069713
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KEYWORD
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nonn,base
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AUTHOR
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Amarnath Murthy, Apr 08 2002
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EXTENSIONS
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Edited and extended by Robert G. Wilson v, Apr 12 2002
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STATUS
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approved
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