login
Smallest prime of additive persistence n.
0

%I #16 Oct 18 2023 10:06:11

%S 2,11,19,199,29998999999999999999999

%N Smallest prime of additive persistence n.

%C a(5) >= 29*10^2222222222222222222221-1, the next number of additive persistence 5 after A006050(5). (a(5) is not equal to A006050(5) because that number is divisible by 313.) - _Pontus von Brömssen_, Oct 17 2023

%D H. J. Hindin, The additive persistence of a number, J. Rec. Math., 7 (No. 2, 1974), 134-135.

%H N. J. A. Sloane, <a href="http://neilsloane.com/doc/persistence.html">The persistence of a number</a>, J. Recreational Math., 6 (1973), 97-98.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/AdditivePersistence.html">Additive Persistence</a>

%F a(n) >= A006050(n). - _Pontus von Brömssen_, Oct 17 2023

%e a(2) = 19, 19 -> 10 -> 1, so 2 summation steps are required to reach a single-digit number.

%Y Cf. A003001, A045646, A006050.

%K hard,nonn,base

%O 0,1

%A _Shyam Sunder Gupta_, Feb 23 2002