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Compute the commas sequence starting at 1, as in A121805, except do the calculations in hexadecimal. The terms are written here in decimal.
1

%I #25 Nov 18 2023 18:08:38

%S 1,18,53,141,350,576,578,612,678,777,924,1120,1124,1192,1325,1539,

%T 1593,1743,1990,2094,2327,2448,2457,2611,2669,2888,3027,3087,3340,

%U 3545,3703,3829,3924,4003,4066,4099,4148,4213,4294,4391,4504,4633,4778,4939,5116,5309,5518

%N Compute the commas sequence starting at 1, as in A121805, except do the calculations in hexadecimal. The terms are written here in decimal.

%C When written in hexadecimal the terms are 1, 12, 35, 8D, 15E, 240, 242, 264, 2A6, 309, 39C, 460, 464, 4A8, 52D, 603, 639, 6CF, 7C6, 82E, 917, 990, 999, A33, A6D, B48, BD3, C0F, D0C, DD9, ...

%C Finite with last term a(144693554136426354) = 18446744073709551480, which is FFFFFFFFFFFFFF78 in hexadecimal. - _Michael S. Branicky_, Nov 18 2023

%H Michael S. Branicky, <a href="/A367345/b367345.txt">Table of n, a(n) for n = 1..100000</a>

%e See A367344 for examples of similar calculations in base 8.

%o (Python)

%o from itertools import islice

%o from sympy.ntheory.factor_ import digits

%o def agen(b=16): # generator of terms

%o an, y = 1, 1

%o while y < b:

%o yield an

%o an, y = an + b*(an%b), 1

%o while y < b:

%o if str(digits(an+y, b)[1]) == str(y):

%o an += y

%o break

%o y += 1

%o print(list(islice(agen(), 50))) # _Michael S. Branicky_, Nov 16 2023

%Y Cf. A121805, A367343, A367344.

%K nonn,base,fini

%O 1,2

%A _N. J. A. Sloane_, Nov 15 2023, following a suggestion from _William Cheswick_