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A319406 Write n-th prime in binary, then increase each run of 0's by one 0, and increase each run of 1's by one 1. a(n) is the decimal equivalent of the result.

%I A319406 #14 Dec 07 2021 10:48:25
%S A319406 12,7,51,15,103,115,195,199,207,243,63,1587,1635,1639,415,1843,487,
%T A319406 499,775,783,3171,799,3271,3299,899,3635,911,3687,3699,963,255,1543,
%U A319406 6243,6247,25395,6351,6387,6535,6543,26227,6599,26419,1663,1795,7219,1807,7367
%N A319406 Write n-th prime in binary, then increase each run of 0's by one 0, and increase each run of 1's by one 1. a(n) is the decimal equivalent of the result.
%C A319406 Apply A175046 to the primes.
%H A319406 Rémy Sigrist, <a href="/A319406/b319406.txt">Table of n, a(n) for n = 1..10000</a>
%o A319406 (Python)
%o A319406 from sympy import prime
%o A319406 def a(n):
%o A319406     b = bin(prime(n))[2:]
%o A319406     return int(b.replace("01", "001").replace("10", "110") + b[-1], 2)
%o A319406 print([a(n) for n in range(1, 48)]) # _Michael S. Branicky_, Dec 07 2021
%Y A319406 Cf. A175046.
%Y A319406 A companion to A318923.
%K A319406 nonn,base
%O A319406 1,1
%A A319406 _N. J. A. Sloane_, Sep 19 2018
%E A319406 More terms from _Rémy Sigrist_, Sep 20 2018