A030622 Powers of 2 grouped in pairs of two digits (version 1).

24, 81, 63, 26, 41, 28, 25, 65, 12, 10, 24, 20, 48, 40, 96, 81, 92, 16, 38, 43, 27, 68, 65, 53, 61, 31, 7, 22, 62, 14, 45, 24, 28, 81, 4, 85, 76, 20, 97, 15, 24, 19, 43, 4, 83, 88, 60, 81, 67, 77, 21, 63, 35, 54, 43, 26, 71, 8, 86, 41, 34, 21, 77, 28, 26, 84, 35, 45, 65

Offset: 1

Author

Alexei Kozlowski (bros(AT)spf.minsk.by)

Keywords

• nonn
• base
• easy

Comments

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

Examples

			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.
		

Crossrefs

Cf. A030623, A030624, A000079, A000455.

Programs

Mathematica

FromDigits/@Partition[Flatten[IntegerDigits[2^Range[32]]], 2] (* Alonso del Arte, Mar 28 2020 *)

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

Extensions

More terms from Douglas Winston (douglas.winston(AT)srupc.com), Nov 06 2003