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 A128717 Primes that yield another prime if one adds either the sum of its digits or the product of its digits. 1
 101, 103, 163, 233, 293, 307, 431, 499, 509, 563, 617, 701, 743, 1009, 1049, 1061, 1087, 1409, 1423, 1483, 1489, 1601, 1607, 1801, 1867, 2017, 2039, 2053, 2273, 2543, 2633, 2903, 3041, 3067, 3089, 3449, 3607, 4013, 4057, 4079, 4211, 4217, 4273, 4507 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE 163 + (1+6+3) = 173, 163 + 1*6*3 = 181; 173 and 181 are prime numbers. MAPLE filter:= proc(n) local S;   S:= convert(n, base, 10);   isprime(n+convert(S, `+`)) and isprime(n+convert(S, `*`)) end proc: A:= NULL: p:= 2: while p < 10000 do   if filter(p) then A:= A, p fi;   p:= nextprime(p) od: A; # Robert Israel, Jul 12 2017 MATHEMATICA Select[Prime[Range[500]], PrimeQ[ # + Plus @@ IntegerDigits[ # ]] && PrimeQ[ # + Times @@ IntegerDigits[ # ]] &] PROG (PARI) isok(n) = isprime(n) && (isprime(n+sumdigits(n)) && ((d=digits(n)) && isprime(n+prod(k=1, #d, d[k])))); \\ Michel Marcus, Jul 12 2017 CROSSREFS Cf. A048519. Sequence in context: A176929 A330563 A060400 * A111348 A081649 A126118 Adjacent sequences:  A128714 A128715 A128716 * A128718 A128719 A128720 KEYWORD base,easy,nonn AUTHOR J. M. Bergot, Jun 27 2007 EXTENSIONS Edited, corrected and extended by Stefan Steinerberger, Jul 14 2007 STATUS approved

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Last modified September 24 17:09 EDT 2020. Contains 337321 sequences. (Running on oeis4.)