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A167631
Emirps A006567 with a sum of digits and a number of digits which are both primes.
0
113, 157, 179, 199, 311, 337, 359, 733, 739, 751, 937, 953, 971, 991, 10039, 10079, 10091, 10253, 10273, 10321, 10343, 10453, 10457, 10459, 10499, 10613, 10639, 10651, 10781, 10853, 10859, 10891, 10909, 11003, 11083, 11159, 11197, 11243
OFFSET
1,1
COMMENTS
Subsequence of A006567 and A028834. - R. J. Mathar, Nov 12 2009
EXAMPLE
113 and 311 are distinct primes, and 3 (number of digits) and 5 (1+1+3) are also primes.
PROG
(PARI) sod(n)=my(s=0); while(n>9, s+=n%10; n\=10); s+n
R(n)=my(v=eval(Vec(Str(n))), s=0); forstep(i=#v, 1, -1, s=10*s+v[i]); s
isA167631(n)=my(r); isprime(#Str(n)) && isprime(sod(n)) && isprime(n) && isprime(r=R(n)) && n!=r \\ Charles R Greathouse IV, Nov 10 2009
CROSSREFS
Sequence in context: A102833 A136078 A230255 * A264778 A142303 A152929
KEYWORD
base,nonn
AUTHOR
Claudio Meller, Nov 07 2009
EXTENSIONS
Edited by Charles R Greathouse IV and R. J. Mathar, Nov 10 2009
STATUS
approved