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A052020 Sum of digits of n is a prime proper factor of n. 7
12, 20, 21, 30, 50, 70, 102, 110, 111, 120, 133, 140, 200, 201, 209, 210, 230, 247, 300, 308, 320, 322, 364, 407, 410, 476, 481, 500, 506, 511, 605, 629, 700, 704, 715, 782, 803, 832, 874, 902, 935, 1002, 1010, 1011, 1015, 1020, 1040, 1066, 1088, 1100, 1101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For each prime p there are infinitely many terms with sum of digits p. - Robert Israel, Feb 26 2017

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

filter:= proc(n) local s;

  s:= convert(convert(n, base, 10), `+`);

  isprime(s) and (n mod s = 0)

end proc:

select(filter, [$10..10^4]); # Robert Israel, Feb 26 2017

CROSSREFS

Cf. A052018, A052019, A052021, A052022, A007953, A005349, A028834.

Sequence in context: A171795 A170806 A038528 * A075078 A050421 A206552

Adjacent sequences:  A052017 A052018 A052019 * A052021 A052022 A052023

KEYWORD

nonn,base,easy

AUTHOR

Patrick De Geest, Nov 15 1999.

STATUS

approved

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Last modified November 16 07:06 EST 2018. Contains 317258 sequences. (Running on oeis4.)