[seqfan] Primes with strokes
Éric Angelini
eric.angelini at skynet.be
Thu Nov 21 16:41:59 CET 2019
(This message was published by mistake
on Math-Fun -- again, with no answer)
Hello Math-Fun, I was wondering if this seq S was sound:
"Put a stroke behind every prime digit. Any integer formed
by the concatenated digits between two strokes is prime."
S = 1,3,2,4,7,5,6,8,9,10,11,14,16,18,83,13,17,,...
The same seq with the strokes:
S = 1,3,\2,\4,7\,5,\6,8,9,10,11,14,16,18,83\,13\,17\,...
If I'm not wrong, S is the lexicographically first seq
of distinct positive terms with this property.
The successive primes are:
13, 2, 47, 5, 689101114161883, 13, 17,...
What do you think?
Best,
É.
More information about the SeqFan
mailing list