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 A199396 Binary XOR of (3^k - 1)/2 as k varies from 1 to n. 3
 1, 5, 8, 32, 89, 309, 1392, 2464, 12241, 23685, 66936, 329856, 598377, 2972885, 4204000, 17321536, 47254689, 156943365, 737779176, 1276350496, 6369950073, 12290868597, 35051319632, 175157734688, 319624706161, 1569854375813, 2311734655064, 9333158201280, 25600877525257 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Paul D. Hanna, Table of n, a(n) for n = 1..365 EXAMPLE a(2) = (3^1-1)/2 XOR (3^2-1)/2 = 1 XOR 4 = 5; a(3) = (3^1-1)/2 XOR (3^2-1)/2 XOR (3^3-1)/2 = 1 XOR 4 XOR 13 = 8; a(4) = (3^1-1)/2 XOR (3^2-1)/2 XOR (3^3-1)/2 XOR (3^4-1)/2 = 1 XOR 4 XOR 13 XOR 40 = 32. MATHEMATICA FoldList[BitXor, Table[(3^n - 1)/2, {n, 1, 29}]] (* Vladimir Reshetnikov, Nov 02 2015 *) PROG (PARI) {a(n)=if(n<=0, 0, bitxor(a(n-1), (3^n-1)/2))} CROSSREFS Cf. A199397, A199403, A199402, A000975. Sequence in context: A002536 A068981 A099631 * A275003 A032790 A187997 Adjacent sequences: A199393 A199394 A199395 * A199397 A199398 A199399 KEYWORD nonn AUTHOR Paul D. Hanna, Nov 05 2011 STATUS approved

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Last modified December 11 11:45 EST 2023. Contains 367725 sequences. (Running on oeis4.)