A352088 - OEIS

%I #4 Mar 05 2022 01:07:17

%S 0,1,3,5,45,2193,7671,35889,53835,74825,3026205,31953871,86582437,

%T 117169915,128873391,701373669,868430067,15262037703,45305389845,

%U 104484026691,614071181169,14894476590363,24382189266573,86808432666553,869188423288227,1352557858988953

%N Numbers whose binary and minimal tribonacci representations are both palindromic.

%e The first 5 terms are:

%e   n  a(n)  A007088(a(n))  A278038(a(n))

%e   -------------------------------------

%e   1     0              0              0

%e   2     1              1              1

%e   3     3             11             11

%e   4     5            101            101

%e   5    45         101101        1000001

%t t[1] = 1; t[2] = 2; t[3] = 4; t[n_] := t[n] = t[n - 1] + t[n - 2] + t[n - 3]; tribPalQ[n_] := Module[{s = {}, m = n, k}, While[m > 0, k = 1; While[t[k] <= m, k++]; k--; AppendTo[s, k]; m -= t[k]; k = 1]; PalindromeQ[FromDigits @ IntegerDigits[Total[2^(s - 1)], 2]]]; Join[{0}, Select[Range[1, 10^5, 2], PalindromeQ[IntegerDigits[#, 2]] && tribPalQ[#] &]]

%Y Intersection of A006995 and A352087.

%Y Cf. A007088, A278038.

%Y Similar sequences: A095309, A331193, A331894, A351713, A351718.

%K nonn,base

%O 1,3

%A _Amiram Eldar_, Mar 04 2022