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A045708 Primes with first digit 2. 23
2, 23, 29, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 2003, 2011, 2017, 2027, 2029, 2039, 2053, 2063, 2069, 2081, 2083, 2087, 2089, 2099, 2111, 2113, 2129, 2131, 2137, 2141, 2143, 2153, 2161, 2179, 2203, 2207, 2213 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

See A045707 for comments on density of these sequences.

MATHEMATICA

Select[Table[Prime[n], {n, 3000}], First[IntegerDigits[#]]==2 &] (* Vincenzo Librandi, Aug 08 2014 *)

PROG

(Haskell)

a045708 n = a045708_list !! (n-1)

a045708_list = filter ((== 2) . a000030) a000040_list

-- Reinhard Zumkeller, Mar 16 2012

(MAGMA) [p: p in PrimesUpTo(2300) | Intseq(p)[#Intseq(p)] eq 2]; // Vincenzo Librandi, Aug 08 2014

CROSSREFS

Cf. A000040.

For primes with initial digit d (1 <= d <= 9) see A045707, A045708, A045709, A045710, A045711, A045712, A045713, A045714, A045715; A073517, A073516, A073515, A073514, A073513, A073512, A073511, A073510, A073509

Cf. A000030, subsequence of A208272.

Column k=2 of A262369.

Sequence in context: A107148 A062653 A208272 * A090150 A106102 A053232

Adjacent sequences:  A045705 A045706 A045707 * A045709 A045710 A045711

KEYWORD

nonn,base,easy

AUTHOR

Felice Russo

EXTENSIONS

More terms from Erich Friedman.

Offset fixed by Reinhard Zumkeller, Mar 15 2012

STATUS

approved

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Last modified September 23 17:44 EDT 2017. Contains 292362 sequences.