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 A027705 Primes with odd number of 1's in binary expansion such that next prime has even number of 1's. 4
 2, 13, 19, 41, 47, 67, 79, 97, 109, 137, 157, 193, 251, 271, 283, 307, 313, 331, 367, 379, 397, 443, 457, 463, 499, 521, 541, 569, 587, 617, 641, 661, 677, 733, 743, 769, 787, 809, 829, 859, 877, 883, 929, 971, 1009, 1021, 1039, 1051, 1087, 1109, 1129, 1171, 1213, 1231, 1259, 1279, 1291 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE N:=1000: # to get all terms in the first N primes Res:= NULL: w:= 0: p:= 0: for i from 1 to N+1 do    q:= nextprime(p);    v:= convert(convert(q, base, 2), `+`) mod 2;    if w = 1 and v = 0 then Res:= Res, p fi;    p:= q; w:= v; od: Res; # Robert Israel, Dec 29 2016 CROSSREFS Sequence in context: A020601 A298051 A298656 * A296938 A296199 A121181 Adjacent sequences:  A027702 A027703 A027704 * A027706 A027707 A027708 KEYWORD nonn AUTHOR EXTENSIONS More terms from Scott Lindhurst (ScottL(AT)alumni.princeton.edu) Offset changed by Robert Israel, Dec 29 2016 STATUS approved

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Last modified December 9 00:32 EST 2019. Contains 329871 sequences. (Running on oeis4.)