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A176012
Chen primes A109611(k) which have the same sum-of-digits as their index k.
3
227, 827, 1201, 1621, 2179, 2333, 2441, 2711, 3041, 3251, 3329, 3541, 5147, 5167, 5701, 5711, 6131, 6661, 6833, 7321, 7331, 8501, 9209, 9239, 10271, 13807, 14251, 14449, 14629, 15731, 15761, 16007, 16139, 16619, 16741, 17291, 19421, 20231, 20441, 20507, 22441
OFFSET
1,1
COMMENTS
The associated indices k are:
38, 98, 130, 163, 199, 209, 218, 236, 260, 272, 278, 292, 386, 388, 418, 419, 443, 469, 479, 508,...
The indices of A109611(k) in the primes A000040 are A000720(A109611(k)) =
49, 144, 197, 257, 327, 345, 362, 395, 436, 458, 469, 496, 686, 688, 751, 752, 799, 859, 880, 933, 934, 1060, ..
Some entries are also Honaker primes (A033548): 2441, 5701, 5711, 15761, 26119, 31517, 34471, 37019, 44221,...
REFERENCES
M. du Sautoy: Die Musik der Primzahlen: Auf den Spuren des groessten Raetsels der Mathematik, Beck, 4. Auflage, 2005
LINKS
B. Green and T. Tao, Restriction Theory of the Selberg Sieve, with Applications, J. Théor. Nombres Bordeaux 18, 2006.
FORMULA
{A109611(k): A007953(A109611(k)) = A007953(k) }.
EXAMPLE
a(1) = 227 = A109611(38) where 2+2+7 = 11 = 3+8.
a(2) = 827 = A109611(98), where 8+2+7 =17= 9+8.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 06 2010
EXTENSIONS
9241 replaced by 9239, and lists of examples reduced by R. J. Mathar, Jun 07 2010
STATUS
approved