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A230255
Emirps whose sum of digits is prime.
1
113, 157, 179, 199, 311, 337, 359, 733, 739, 751, 937, 953, 971, 991, 1031, 1033, 1091, 1097, 1103, 1109, 1181, 1213, 1217, 1231, 1237, 1259, 1279, 1301, 1321, 1381, 1439, 1453, 1471, 1499, 1523, 1583, 1619, 1657, 1723, 1741, 1811, 1831, 1901, 1949, 3011, 3019
OFFSET
1,1
LINKS
EXAMPLE
a(6)= 337 is emirp. Sum of digits= 3+3+7= 13 which is prime.
a(11)= 937 is emirp. Sum of digits= 9+3+7= 19 which is prime.
MAPLE
with(StringTools):KD:= proc() local a, b, d; a:=ithprime(n); b:=parse(Reverse(convert(a, string))); d:=add( i, i = convert((a), base, 10))(a); if a<>b and isprime(b) and isprime(d) then return(a):fi; end: seq(KD(), n=1..2000);
MATHEMATICA
Select[Prime[Range[500]], !PalindromeQ[#]&&AllTrue[{IntegerReverse[#], Total[ IntegerDigits[ #]]}, PrimeQ]&] (* Harvey P. Dale, Nov 01 2022 *)
CROSSREFS
Cf. A006567 (emirps: primes whose reversal is different prime).
Cf. A082806 (palindromic primes: sum of digits is prime).
Cf. A178092 (emirps: digital sum is emirp).
Sequence in context: A164920 A102833 A136078 * A167631 A264778 A142303
KEYWORD
nonn,base,less
AUTHOR
K. D. Bajpai, Oct 14 2013
STATUS
approved