A030144 - OEIS

A030144

Primes in which parity of digits alternates.

2, 3, 5, 7, 23, 29, 41, 43, 47, 61, 67, 83, 89, 101, 103, 107, 109, 127, 149, 163, 167, 181, 307, 347, 349, 367, 383, 389, 503, 509, 521, 523, 541, 547, 563, 569, 587, 701, 709, 727, 743, 761, 769, 787, 907, 929, 941, 947, 967, 983, 2129, 2141, 2143, 2161, 2309

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OFFSET

1,1

LINKS

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

FORMULA

A010051(a(n)) * A228710(a(n)) = 1. - Reinhard Zumkeller, Aug 31 2013

EXAMPLE

2129 is a term as 2, 1, 2 and 9 have even and odd parity alternately.

MATHEMATICA

Join[{2, 3, 5, 7}, Select[Prime[Range[400]], Union[Abs[Differences[Boole/@ EvenQ[ IntegerDigits[#]]]]] == {1}&]] (* Harvey P. Dale, Jul 26 2011 *)

PROG