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%I #9 Mar 28 2020 19:21:05
%S 24,81,63,26,41,28,25,65,12,10,24,20,48,40,96,81,92,16,38,43,27,68,65,
%T 53,61,31,7,22,62,14,45,24,28,81,4,85,76,20,97,15,24,19,43,4,83,88,60,
%U 81,67,77,21,63,35,54,43,26,71,8,86,41,34,21,77,28,26,84,35,45,65
%N Powers of 2 grouped in pairs of two digits (version 1).
%C When a 0 occurs as the most significant digit of the pair, it is simply ignored, e.g., "07" becomes just 7. The following pairs are unaffected. - _Alonso del Arte_, Mar 28 2020
%e The first few powers of 2 corresponding to positive exponents are 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048. The digits are 2, 4, 8, 1, 6, 3, 2, 6, 4, 1, 2, 8, 2, 5, 6, 5, 1, 2, 1,0, 2, 4, 2, 0, 4, 8. Grouping them in pairs, we obtain 24, 81, 63, 26, 41, 28, 25, 65, 12, 10, 24, 20, 48.
%t FromDigits/@Partition[Flatten[IntegerDigits[2^Range[32]]], 2] (* _Alonso del Arte_, Mar 28 2020 *)
%o (Scala) (List.fill(32)(2: BigInt)).scanLeft(1: BigInt)(_ * _).filter(_ > 1).map(_.toString.toCharArray).flatten.sliding(2, 2).map(_.toArray).toList.map(new String(_)).map(Integer.parseInt(_)) // _Alonso del Arte_, Mar 28 2020
%Y Cf. A030623, A030624, A000079, A000455.
%K nonn,base,easy
%O 1,1
%A Alexei Kozlowski (bros(AT)spf.minsk.by)
%E More terms from Douglas Winston (douglas.winston(AT)srupc.com), Nov 06 2003