A225303 - OEIS

A225303

Primes of the form p + (product of digits of p), where p is a prime.

29, 47, 67, 101, 103, 107, 109, 181, 251, 293, 307, 331, 347, 401, 409, 431, 443, 457, 491, 503, 509, 547, 593, 601, 607, 631, 653, 659, 673, 701, 709, 743, 809, 823, 827, 839, 907, 929, 971, 977, 1009, 1013, 1019, 1021, 1031, 1033, 1039, 1049, 1051, 1061, 1063, 1069, 1087, 1091

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Primes generated by A157677.

LINKS

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

EXAMPLE

29 is in the list since 29 = 23 + (2*3).

MAPLE

f:= proc(n) local L, v;

if not isprime(n) then return NULL fi;

L:= convert(n, base, 10);

if member(0, L) then return n fi;

v:= n + convert(L, `*`);

if isprime(v) then v else NULL fi

end proc:

N:= 2000: # to get all terms <= N

S:= {}:

for n from 3 by 2 to N do

v:= f(n);

if v <> NULL and v <= N then S:= S union {v} fi;

od:

sort(convert(S, list)); # Robert Israel, Jun 25 2019

MATHEMATICA

Sort[DeleteDuplicates[Select[Table[p=Prime[n]; p+Times@@IntegerDigits[p], {n, 175}], PrimeQ]]]

Select[Table[p+Times@@IntegerDigits[p], {p, Prime[Range[ 200]]}], PrimeQ]// Union (* Harvey P. Dale, Sep 21 2019 *)

CROSSREFS

Cf. A157677.

Sequence in context: A110054 A104912 A104913 * A344466 A102852 A138052

Adjacent sequences: A225300 A225301 A225302 * A225304 A225305 A225306

KEYWORD

nonn,base

AUTHOR

Jayanta Basu, May 05 2013

EXTENSIONS

1049,1051,1061,1063,1069 and 1087 inserted by Robert Israel, Jun 25 2019

STATUS

approved