A007284 Horizontally symmetric numbers.

0, 1, 3, 8, 10, 11, 13, 18, 30, 31, 33, 38, 80, 81, 83, 88, 100, 101, 103, 108, 110, 111, 113, 118, 130, 131, 133, 138, 180, 181, 183, 188, 300, 301, 303, 308, 310, 311, 313, 318, 330, 331, 333, 338, 380, 381, 383, 388, 800, 801, 803, 808, 810, 811, 813, 818

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy
• base

References

• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• Indranil Ghosh, Table of n, a(n) for n = 0..50000

Crossrefs

Cf. A046031.

Programs

Python

allowed = ("0", "1", "3", "8")
def a(n):
    return all(x in allowed for x in str(n))
print([i for i in range(50000) if a(i)])
# Indranil Ghosh, Feb 03 2017

Formula

Numbers using only digits 0, 1, 3 and 8.

Extensions

More terms from Henry Bottomley, Feb 14 2000