Problems & Puzzles: Puzzles Puzzle 247. Consecutive Smith numbers The largest sequence of consecutive Smith numbers was gotten by Shyam Sunder Gupta approximately on February 2001 as an answer to a not very elegant puzzle of these pages (Puzzle 107). These days the largest sequence found by Shyam was composed by 5 members (4, 728, 73615, 4463535, 15966114) published as A059754, and thus remained the same until two days ago when I tried to cover a small range over the scanned by Shyam (<4x10^8). Unexpectedly the sixth member of this sequence came up very fast (24 hours later) in my not very powerful PC: 2050918644. So I think that with the new speedy machines we have nowadays we should get one or two more terms for this sequence. Q1 Find more terms to A059754 As you know prime numbers are trivial Smith numbers. What if include primes as Smith numbers discarding the compositeness from its definition?. I have gotten the following sequence (defining each member as the earliest number of a sequence of k consecutive Smith numbers, primes included as Smith numbers) 2, 2, 2, 2, 1458855, 1790478, 429990136, ? Q2 Find more terms to the last sequence Solution: Faride Firoozbakht reports:
*** Shyam wrote (July 2007):
*** J. K. Andersen wrote (April 08):
*** Giovanni Resta wrote on January 2014:
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