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A225303 Primes of the form p + (product of digits of p), where p is a prime. 3
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
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
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

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Last modified February 21 22:50 EST 2024. Contains 370239 sequences. (Running on oeis4.)