Search: id:A100672 Results 1-1 of 1 results found. %I A100672 %S A100672 1,1,0,1,1,0,0,1,1,0,1,0,0,1,1,0,1,0,1,1,0,1,1,0,0,0,1,1,0,0,1,1,0,1,0, %T A100672 1,0,1,1,0,1,0,1,0,0,1,1,1,1,0,0,1,0,1,0,1,0,1,0,0,1,0,1,1,0,0,1,0,1,0, %U A100672 0,1,1,0,1,1,0,0,0,0,1,0,1,0,1,1,0,0,0,1,1,1,1,1,1,1,0,0,1,0,1,0,1,0,1 %N A100672 Second least-significant bit in the binary expansion of the k-th prime. %C A100672 a(n)=1 iff Prime[n] is a member of A045326 (equivalently, iff Prime[n]-3 is divisible by 4) %H A100672 Eric Weisstein's World of Mathematics, Fermat's 4n Plus 1 Theorem. %H A100672 Eric Weisstein's World of Mathematics, Gaussian Prime. %F A100672 a(n) := Mod[Prime[n], 4] != 2 %e A100672 a(2)=1 because Prime[2]=11_2 (in binary; decimal = 3_10) and its 2^1 bit is 1. %e A100672 a(3)=0 because Prime[3]=101_2 (in binary; decimal = 5_10) and its 2^1 bit is 0. %t A100672 Table[Reverse[RealDigits[Prime[k], 2][[1]]][[2]], {k, 1, 128}] %Y A100672 Cf. A045326. %Y A100672 Cf. A002144, A002145. %Y A100672 equal to 1 minus A098033 [From Steven G. Johnson (stevenj(AT)math.mit.edu), Sep 18 2008] %Y A100672 Sequence in context: A123594 A145006 A080813 this_sequence A079559 A014577 A157926 %Y A100672 Adjacent sequences: A100669 A100670 A100671 this_sequence A100673 A100674 A100675 %K A100672 base,nonn %O A100672 1,1 %A A100672 Joseph Biberstine (jrbibers(AT)indiana.edu), Dec 06 2004 Search completed in 0.001 seconds