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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

User: William Cheswick

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William Cheswick has authored 1 sequences.

A367345 Compute the commas sequence starting at 1, as in A121805, except do the calculations in hexadecimal. The terms are written here in decimal.

Original entry on oeis.org

1, 18, 53, 141, 350, 576, 578, 612, 678, 777, 924, 1120, 1124, 1192, 1325, 1539, 1593, 1743, 1990, 2094, 2327, 2448, 2457, 2611, 2669, 2888, 3027, 3087, 3340, 3545, 3703, 3829, 3924, 4003, 4066, 4099, 4148, 4213, 4294, 4391, 4504, 4633, 4778, 4939, 5116, 5309, 5518
Offset: 1

Author

N. J. A. Sloane, Nov 15 2023, following a suggestion from William Cheswick

Keywords

Comments

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, ...
Finite with last term a(144693554136426354) = 18446744073709551480, which is FFFFFFFFFFFFFF78 in hexadecimal. - Michael S. Branicky, Nov 18 2023

Examples

			See A367344 for examples of similar calculations in base 8.
		

Crossrefs

Programs

  • Python
    from itertools import islice
    from sympy.ntheory.factor_ import digits
    def agen(b=16): # generator of terms
        an, y = 1, 1
        while y < b:
            yield an
            an, y = an + b*(an%b), 1
            while y < b:
                if str(digits(an+y, b)[1]) == str(y):
                    an += y
                    break
                y += 1
    print(list(islice(agen(), 50))) # Michael S. Branicky, Nov 16 2023