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A337752
a(n) is the smallest Moran number m for which m/digsum(m) = prime(n) or 0 if no such number exists.
1
18, 27, 45, 21, 198, 117, 153, 114, 207, 261, 372, 111, 738, 516, 423, 954, 531, 732, 201, 1278, 511, 711, 1494, 801, 1164, 1818, 1236, 1926, 1090, 1017, 1016, 2358, 1233, 1251, 1341, 1812, 1413, 1141, 1503, 0, 1611, 1810, 3438, 2316, 3546, 3184, 2532, 2007
OFFSET
1,1
COMMENTS
If prime(k) is in A130338 then a(k) = 0.
LINKS
EXAMPLE
A001101(1) = 18 and 18 / digsum(18) = 18/9 = 2 = prime(1), so a(1) = 18.
A001101(2) = 21 and 21 / digsum(21) = 21/3 = 7 = prime(4), so a(4) = 21.
A001101(3) = 27 and 27 / digsum(27) = 27/9 = 3 = prime(2), so a(2) = 27.
A001101(5) = 45 and 45 / digsum(45) = 45/9 = 5 = prime(3), so a(3) = 45.
A130338(1) = 173 = prime(40), so a(40) = 0.
PROG
(Magma) f:=func<n, m| m mod &+Intseq(m) eq 0 and (m div &+Intseq(m) eq NthPrime(n))>; a:=[]; for n in [1..50] do m:=NthPrime(n); while m le 9*NthPrime(n)*(Log(10, m)+1) and not f(n, m) do m:=m+NthPrime(n); end while; if (m div &+Intseq(m) eq NthPrime(n)) then Append(~a, m); else Append(~a, 0); end if; end for; a;
CROSSREFS
Cf. A001101 (Moran numbers), A007953 (digsum), A130338.
Sequence in context: A239878 A065751 A345309 * A279108 A038632 A138336
KEYWORD
nonn,base
AUTHOR
Marius A. Burtea, Sep 18 2020
STATUS
approved