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

Author

Matt C. Anderson, Oct 09 2016

Keywords

• nonn
• base

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.

Examples

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

Links

• Wikipedia, Lychrel number

Crossrefs

Cf. A004086.

Almost the same as A006960.

See index entries at A023108.

Programs

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 *)

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

Formula

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

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