A042983 - OEIS

A042983

Numbers n > 99 with following property: form a sequence whose initial terms are the t digits of n, later terms given by rule b(i+1) = b(i) + product of t-1 previous terms; then n itself appears in the sequence.

%I #17 Oct 19 2013 15:07:52

%S 205,302,1220,1757,3505,4484,59445,80005,99543,393544,1545283,

%T 31593249,33252489,184577126,139316682243,793957132718,3827180840962

%N Numbers n > 99 with following property: form a sequence whose initial terms are the t digits of n, later terms given by rule b(i+1) = b(i) + product of t-1 previous terms; then n itself appears in the sequence.

%C a(18) > 10^13. - _Giovanni Resta_, Oct 19 2013

%e 1757 is a 4-digit term since sequence is 1, 7, 5, 7, 1*7*5+7 =42, 7*5*7+42 = 287, 5*7*42+287 = 1757.

%Y Cf. A007629.

%K nonn,base,more

%O 1,1

%A _Denis Borris_

%E a(15)-a(17) from _Giovanni Resta_, Oct 19 2013