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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 (list; graph; refs; listen; history; text; internal format)
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

Table of n, a(n) for n=1..41.

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

Cf. A033548, A109611, A174924.

Sequence in context: A088788 A142390 A142219 * A031693 A158228 A209843

Adjacent sequences:  A176009 A176010 A176011 * A176013 A176014 A176015

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

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Last modified October 18 01:39 EDT 2021. Contains 348065 sequences. (Running on oeis4.)