cp's OEIS Frontend

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.

A176630 Nonpalindromic numbers whose binary representation when reversed is the same as binary representation of the number reversed in decimal.

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%I A176630 #15 Apr 08 2025 21:55:32
%S A176630 92,732,759,957,5485,5845,71869,77360,96817,319773,377913,13162800,
%T A176630 39781062,79497594,94729789,98792749,144579540,1231493321,1233941321,
%U A176630 7075293947,7493925707,32817543720,71461803829,92830816417,169709554740,1432254694771,1774964522341
%N A176630 Nonpalindromic numbers whose binary representation when reversed is the same as binary representation of the number reversed in decimal.
%C A176630 The binary representation of a decimal number, when reversed, is also the reverse of the decimal number.
%F A176630 Intersection of A029742 and A081434. - _Andrew Howroyd_, Jan 14 2020
%e A176630 92 = 1011100 mirrors 0011101 = 29.
%e A176630 732 = 1011011100 mirrors 0011101101 = 237.
%t A176630 Select[Range[10^6], And[! PalindromeQ@ #, Drop[#, LengthWhile[#, # == 0 &]] &@ Reverse@ IntegerDigits[#, 2] === IntegerDigits[IntegerReverse[#], 2]] &] (* _Michael De Vlieger_, Dec 29 2020 *)
%o A176630 (PARI) is(k)={my(t=fromdigits(Vecrev(digits(k,10)),10)); t<>k && t == fromdigits(Vecrev(digits(k,2)),2)} \\ _Andrew Howroyd_, Jan 14 2020
%o A176630 (Python)
%o A176630 def agen():
%o A176630   k = 0
%o A176630   while True:
%o A176630     strk = str(k)
%o A176630     revstrk = strk[::-1]
%o A176630     if revstrk != strk:
%o A176630       if int(revstrk) == int((bin(k)[2:])[::-1], 2):
%o A176630         yield k
%o A176630     k += 1
%o A176630 g = agen()
%o A176630 print([next(g) for i in range(11)]) # _Michael S. Branicky_, Dec 29 2020
%Y A176630 Cf. A029742, A081434.
%K A176630 nonn,base
%O A176630 1,1
%A A176630 _Gil Broussard_, Apr 22 2010
%E A176630 Name clarified and a(12)-a(17) from _Andrew Howroyd_, Jan 14 2020
%E A176630 a(18)-a(24) from _Michael S. Branicky_, Dec 29 2020
%E A176630 a(25)-a(27) from _Jinyuan Wang_, Apr 07 2025