A233574
a(n) is the smallest term of either A233010 or A233572 such that |n-a(n)|
0, 1, 2, 2, 4, 3, 4, 6, 8, 6, 6, 8, 8, 7, 12, 8, 10, 9, 10, 13, 12, 13, 16, 20, 16, 18, 26, 18, 18, 20, 18, 18, 20, 20, 18, 26, 20, 24, 26, 21, 24, 21, 26, 43, 32, 24, 28, 26, 28, 43, 30, 27, 28, 27, 28, 54, 30, 39, 40, 32, 32, 43, 32, 39, 40, 39, 40, 43, 36
Offset: 0
Examples
a(19)=13 since 19=13+6=A233010(9)+A233572(3) and 13>6. There is no number in A233010 or A233572 smaller than 13 that satisfies the same condition.
Links
- Lei Zhou, Table of n, a(n) for n = 0..10000
Programs
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Mathematica
BTDigits[m_Integer, g_] := (*This is to determine digits of a number in balanced ternary notation.*) Module[{n = m, d, sign, t = g}, If[n != 0, If[n > 0, sign = 1, sign = -1; n = -n]; d = Ceiling[Log[3, n]]; If[3^d - n <= ((3^d - 1)/2), d++]; While[Length[t] < d, PrependTo[t, 0]]; t[[Length[t] + 1 - d]] = sign; t = BTDigits[sign*(n - 3^(d - 1)), t]]; t]; BTpaleQ[n_Integer] := (*This is to query if a number is an element of sequence A233010.*) Module[{t, trim = n/3^IntegerExponent[n, 3]}, t = BTDigits[trim, {0}]; t == Reverse[t]]; BTrteQ[n_Integer] := (*This is to query if a number is an element of sequence A233572.*) Module[{t, trim = n/3^IntegerExponent[n, 3]}, t = BTDigits[trim, {0}]; DeleteDuplicates[t + Reverse[t]] == {0}]; sa = Select[Range[0, 30000], BTpaleQ[#] &]; (*This is to generate a limited list of A233010.*) sb = Select[Range[0, 30000], BTrteQ[#] &]; (*This is to generate a limited list of A233572.*) range = 68; Table[i1 = 0; i2 = 0; While[If[sa[[i1 + 1]] < sb[[i2 + 1]], i1++; nh = sa[[i1]]; isa = 1, i2++; nh = sb[[i2]]; isa = 0]; (2*nh) < n]; While[If[isa == 0, chk = MemberQ[sa, Abs[n - nh]], chk = MemberQ[sb, Abs[n - nh]]]; ! chk, If[sa[[i1 + 1]] < sb[[i2 + 1]], i1++; nh = sa[[i1]]; isa = 1, i2++; nh = sb[[i2]]; isa = 0]]; If[isa == 0, m = sb[[i2]], m = sa[[i1]]]; m, {n, 0, range}]
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