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A308711 Left-truncatable primes in base-10 bijective numeration. 1
2, 3, 5, 7, 13, 17, 23, 37, 43, 47, 53, 67, 73, 83, 97, 103, 107, 113, 137, 167, 173, 197, 223, 283, 307, 313, 317, 337, 347, 353, 367, 373, 383, 397, 443, 467, 503, 523, 547, 607, 613, 617, 643, 647, 653, 673 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Not identical to A033664; in fact a strict subsequence of A033664. For example, 2003 belongs to A033664 but not to this sequence, since in bijective numerals 2003 is 19X3, whose suffix 9X3 = 1003 = 17 * 59.

LINKS

Robin Houston, Table of n, a(n) for n = 1..8391

Wikipedia, Bijective numeration

PROG

(Sage)

DIGITS = "123456789X"

DECODE = {d: i + 1 for i, d in enumerate(DIGITS)}

def decode(s):

    return reduce(lambda n, c: 10 * n + DECODE[c], s, 0)

def search(s):

    n = decode(s)

    if n > 0:

        if not is_prime(n): return

        yield n

    for digit in DIGITS: yield from search(digit + s)

full = sorted(search(""))

full[:10]

CROSSREFS

Cf. A024785, A033664.

Sequence in context: A234695 A067905 A042993 * A033664 A024785 A069866

Adjacent sequences:  A308708 A308709 A308710 * A308712 A308713 A308714

KEYWORD

nonn,base,easy,fini,full

AUTHOR

Robin Houston, Jun 19 2019

STATUS

approved

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Last modified March 30 15:42 EDT 2020. Contains 333127 sequences. (Running on oeis4.)