Search: id:A029961 Results 1-1 of 1 results found. %I A029961 %S A029961 0,1,2,3,5,55,373,393,666,787,939,7997,53235,55255,55655,57675, %T A029961 506605,1801081,2215122,3826283,3866683,5051505,5226225,5259525, %U A029961 5297925,5614165,5679765,53822835,623010326,954656459,51717171715 %N A029961 Palindromic in bases 4 and 10. %H A029961 P. De Geest, Palindromic numbers beyond base 10 %t A029961 NextPalindrome[n_] := Block[{l = Floor[ Log[10, n] + 1], idn = IntegerDigits[n]}, If[ Union[idn] == {9}, Return[n + 2], If[l < 2, Return[n + 1], If[ FromDigits[ Reverse[ Take[idn, Ceiling[l/2]] ]] FromDigits[ Take[idn, -Ceiling[l/2]]], FromDigits[ Join[ Take[idn, Ceiling[l/2]], Reverse[ Take[idn, Floor[l/2]] ]]], idfhn = FromDigits[ Take[idn, Ceiling[l/ 2]]] + 1; idp = FromDigits[ Join[ IntegerDigits[idfhn], Drop[ Reverse[ IntegerDigits[idfhn]], Mod[l, 2]] ]]] ]]]; palQ[n_Integer, base_Integer] := Block[{idn = IntegerDigits[n, base]}, idn == Reverse[idn]]; l = {0}; a = 0; Do[a = NextPalindrome[a]; If[ palQ[a, 4], AppendTo[l, a]], {n, 1000000}]; l (from Robert G. Wilson v Sep 30 2004) %Y A029961 Cf. A007632, A007633, A029962, A029963, A029964, A029804, A029965, A029966, A029967, A029968, A029969, A029970, A029731, A097855, A099165. %Y A029961 Sequence in context: A114370 A114725 A136340 this_sequence A083665 A084839 A103110 %Y A029961 Adjacent sequences: A029958 A029959 A029960 this_sequence A029962 A029963 A029964 %K A029961 nonn,base %O A029961 1,3 %A A029961 Patrick De Geest (pdg(AT)worldofnumbers.com) Search completed in 0.001 seconds