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A353054 Numbers k such that placing the last digit first gives 2k+1.

%I A353054 #47 Apr 24 2022 02:29:28
%S A353054 1052,26315,15789473,3157894736,421052631578,2105263157894,
%T A353054 36842105263157,1052631578947368421052,26315789473684210526315,
%U A353054 15789473684210526315789473,3157894736842105263157894736,421052631578947368421052631578,2105263157894736842105263157894,36842105263157894736842105263157
%N A353054 Numbers k such that placing the last digit first gives 2k+1.
%C A353054 The digits of all terms appear to be a substring of the digits 105263157894736842 (= A092697(2)) repeated. - _Chai Wah Wu_, Apr 23 2022
%H A353054 Chai Wah Wu, <a href="/A353054/b353054.txt">Table of n, a(n) for n = 1..389</a>
%e A353054 2*1052 + 1 = 2105. Thus, 1052 is in this sequence.
%t A353054 Select[Range[100000000], FromDigits[Prepend[Drop[IntegerDigits[#], -1], Last[IntegerDigits[#]]]] == 2 # + 1 &]
%o A353054 (PARI) f(n) = if (n < 10, n, my(d=digits(n)); fromdigits(concat(d[#d], Vec(d, #d-1))));
%o A353054 isok(m) = f(m) == 2*m+1; \\ _Michel Marcus_, Apr 21 2022
%o A353054 (Python)
%o A353054 from itertools import count, islice
%o A353054 def A353054_gen(): # generator of terms
%o A353054     for l in count(1):
%o A353054         a, b = 10**l-2, 10**(l-1)-2
%o A353054         for m in range(1,10):
%o A353054             q, r = divmod(m*a-1,19)
%o A353054             if r == 0 and b <= q - 2 <= a:
%o A353054                 yield 10*q+m
%o A353054 A353054_list = list(islice(A353054_gen(),20)) # _Chai Wah Wu_, Apr 23 2022
%Y A353054 Other "rotate right" sequences: A035126, A035130.
%Y A353054 Subsequence of A034180.
%K A353054 nonn,base
%O A353054 1,1
%A A353054 _Tanya Khovanova_, Apr 20 2022
%E A353054 a(4)-a(7) from _Amiram Eldar_, Apr 22 2022
%E A353054 a(8)-a(14) from _Chai Wah Wu_, Apr 23 2022