[seqfan] New sequence?

Claudio Meller claudiomeller at gmail.com
Wed Oct 29 21:42:41 CET 2014


Hello SeqFans,
My english is very bad, sorry, I explain a idea similar to Eric Angelini
sequences

Numbers that has the property that every pair of adjacent digits have a
product such is digital root is a prime number

2,3,5,7,12,13,15,17,21,26,27,28,31,34,37,43,44,45,48,51,54,55,56,62,65,68,71,72,73,78,82,84,86,87...
(
​​
​I don´t found it in the OEIS)


1265554 have this property and we want to transform this integer into
another integer having the same property by inserting single digits in this
number (obviously not 0 and 9)
Note that the number has 7 digits and we have 8 positions to put the new
digit

1265554 + 1 (at position 5)  = 12651554 dr(digital root) of products
2,3,3,5,5,7,2
1265554 + 2 (at  position 1) = 21265554 dr 2,2,3,3,7,7,2
1265554 + 3 (at position 8)  = 12655543  dr 2,3,3,7,7,2,3
1265554 + 4 (at position 7)  = 12655544 dr 2,3,3,7,7,2,7
1265554 + 5 (at position 4)  = 12655554 dr 2,3,3,7,7,7,2
1265554 + 6 (at position 6) =  12655654 dr 2,3,3,7,3,3,2
1265554 + 7 (at position 2) =  17265554 dr 7,5,3,3,7,7,2
1265554 + 8 (at position 3) =  12865554 dr 2,7,3,3,7,7,2

So we can insert one different digit in every position to form a new number
with this property .

​Is this the smallest number with this property?​

-- 
Claudio Meller
http://grageasdefarmacia.blogspot.com
http://todoanagramas.blogspot.com/
http://simplementenumeros.blogspot.com/



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