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"Comma sum" sequence: a(n+1)-a(n) = rightmost digit of a(n) + leftmost digit of a(n+1), use smallest possible solution; starting with 396.
5

%I #15 Nov 04 2024 09:30:37

%S 396,406,416,426,436,446,456,466,476,486,496,507,519,533,541,547,559,

%T 573,581,587,599,614,624,634,644,654,664,674,684,694,705,717,731,739,

%U 755,767,781,789,806,820,828,844,856,870,878,894,907,923,935,949,967

%N "Comma sum" sequence: a(n+1)-a(n) = rightmost digit of a(n) + leftmost digit of a(n+1), use smallest possible solution; starting with 396.

%C The starting value 396 is the first which seems to lead to an infinite sequence; most smaller starting values "converge" to a sequence ending in 989, which has no successor. See A230288 for further discussion.

%H Michael S. Branicky, <a href="/A230450/b230450.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/CommaSum.htm">Comma Sums</a>

%H Eric Angelini, <a href="/A230288/a230288.txt">Comma Sums</a> [Cached copy, with permission]

%o (PARI) A230288_vec([396],200)

%o (Python) # uses A230288gen() in A230288

%o from itertools import islice

%o print(list(islice(A230288gen(start=[396]), 123))) # _Michael S. Branicky_, Nov 03 2024

%Y Cf. A230288, A230452, A230453.

%K nonn,base

%O 1,1

%A _M. F. Hasler_, Oct 19 2013