A277338 Reverse and Add! sequence starting with 295.

295, 887, 1675, 7436, 13783, 52514, 94039, 187088, 1067869, 10755470, 18211171, 35322452, 60744805, 111589511, 227574622, 454050344, 897100798, 1794102596, 8746117567, 16403234045, 70446464506, 130992928913, 450822227944, 900544455998, 1800098901007, 8801197801088, 17602285712176, 84724043932847, 159547977975595

Offset

0,1

Comments

Apart from the initial term in both sequences, the same as A006960.

a(0) = 295; a(n+1) = a(n) + A004086(a(n)).

295 is conjectured to be the second smallest initial term which does not lead to a palindrome. Also, 196 is possibly the smallest initial term which does not lead to a palindrome. a(0) = 196 is described in A006960.

Links

Table of n, a(n) for n=0..28.

Wikipedia, Lychrel number

Formula

a(n) = A006960(n) for n >= 1.

a(n) = A243238(295, n+1). - Felix Fröhlich, Nov 20 2016

Example

a(0) = 295
a(1) = 295 + 592 = 887
a(2) = 887 + 788 = 1675
...

Maple

with(StringTools):
revnum := proc (n)
local a, b, c;
description "to REVerse the digits of a NUMber";
a := convert(n, string);
b := Reverse(a);
c := convert(b, decimal, 10)
end proc;
f := 0;
e := 295;
count := 0;
while f <> e do
e := e+f;
f := revnum(e);
count := count+1
end do;

Mathematica

a[1] = 295; a[n_] := a[n] = FromDigits@ Reverse@ IntegerDigits@ # + # &@ a[n - 1]; Array[a, 29] (* Michael De Vlieger, Oct 14 2016 *)

Prog

(PARI) terms(n) = my(x=295, i=0); while(1, print1(x, ", "); x=x+eval(concat(Vecrev(Str(x)))); i++; if(i==n, break))
/* Print initial 30 terms as follows: */
terms(30) \\ Felix Fröhlich, Nov 15 2016

Crossrefs

Cf. A004086.

Almost the same as A006960.

See index entries at A023108.

Sequence in context: A063049 A131274 A074868 * A252083 A279052 A237803

Adjacent sequences: A277335 A277336 A277337 * A277339 A277340 A277341

Keyword

nonn,base

Author

Matt C. Anderson, Oct 09 2016

Status

approved