A352375 - OEIS

%I #20 Mar 29 2022 11:00:35

%S 5,1,2,4,8,7,5,10,11,13,8,16,14,10,11,4,8,7,14,10,11,13,17,7,5,10,11,

%T 13,8,16,14,19,11,13,8,16,14,19,20,13,8,16,14,19,20,13,8,16,14,19,20,

%U 22,8,16,14,19,20,22,17,16,14,19,20,13,17,16,14,19,20,13

%N Sum of digits of A007618.

%D D. R. Kaprekar, Puzzles of the Self-Numbers. 311 Devlali Camp, Devlali, India, 1959.

%H D. R. Kaprekar, <a href="/A003052/a003052_2.pdf">The Mathematics of the New Self Numbers</a>, 1963. [annotated and scanned]

%F a(n) = A007953(A007618(n)).

%F a(n) = A007618(n+1)-A007618(n). - _Chai Wah Wu_, Mar 29 2022

%o (PARI) lista(nn) = my(s, x=5); for(n=1, nn, print1(s=sumdigits(x), ", "); x+=s); \\ _Jinyuan Wang_, Mar 22 2022

%o (Python)

%o from itertools import islice

%o def A352375_gen(): # generator of terms

%o     a = 5

%o     while True:

%o         yield (s := sum(int(d) for d in str(a)))

%o         a += s

%o A352375_list = list(islice(A352375_gen(),20)) # _Chai Wah Wu_, Mar 29 2022

%Y Cf. A007618, A007953.

%K nonn,base

%O 1,1

%A _Mateusz Pasternak_, Mar 14 2022

%E More terms from _Jinyuan Wang_, Mar 22 2022