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%I #30 May 29 2021 10:16:19
%S 0,3,1,3,3,6,10,28,108,1011,32511,9314238,84560776390,
%T 219625370880235960
%N Lionel-Levine-sequence generated by (1,0,0).
%C A011784 allows the addition of a(-1)=0 and a(0)=2 using row A012257(-2)=1 and A012257(-1)=0 resp. row A012257(0)=2. In this sense A011784 / A012257 are "generated" by (1,0), A061892 / A061893 by (1,0,0), A061894 / A061895 by (2,0).
%e a(4) = 3: (1,0,0), (3), (1,1,1), (1,2,3), (1,1,1,2,2,3).
%o (Rexx) /* replace 1 0 0 with 1 0 to get A011784 */
%o S = ''; A = 1 0 0; do N = 1 to 10; T = words( A );
%o S = S word( A, T ); B = A; A = ''; do K = 1 to T;
%o A = A space( copies( K '', word( B, T + 1 - K )));
%o end K; end N; T = words( A ); say S word( A, T ) T;
%Y Cf. A011784, A012257, A061893, A061894.
%K nonn,more
%O 0,2
%A _Frank Ellermann_, May 13 2001
%E a(11) from _Naohiro Nomoto_, May 10 2002
%E a(12) from _Michael Anthony Keyes_, Apr 14 2021
%E a(13) from _Michael Anthony Keyes_, May 13 2021
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