perplexus.info :: Numbers : More Consecutive Semiprimes

More Consecutive Semiprimes (Posted on 2009-09-08)

Consider the series of semiprimes. Now consider the series of numbers representing the Sum Of Digits (SOD) of each semiprime.

(1.) How many times does the number '9' occur, and why?

(2.) What is the smallest semiprime that has the same SOD as the next consecutive semiprime? or prove that there is no pair of consecutive semiprimes that have the same SOD.

No Solution Yet Submitted by Larry

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Subject	Author	Date
re: Puzzle Answer	K Sengupta	2024-01-07 12:10:45
Puzzle Answer	K Sengupta	2023-12-12 06:03:09
re: part 2 (computer solution) UBASIC version	Charlie	2009-09-08 23:58:21
part 2 (computer solution)	Daniel	2009-09-08 12:57:22
part 1 with proof	Daniel	2009-09-08 12:50:03
Answer to part 1	FrankM	2009-09-08 12:48:24

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