This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A320348 #25 Feb 23 2021 10:08:15 %S A320348 1,1,1,2,3,2,4,4,4,6,9,7,13,12,13,16,22,17,28,28,31,36,50,45,63,62,74, %T A320348 78,102,92,123,123,146,148,191,181,228,233,280,283,348,350,420,437, %U A320348 518,523,616,641,727,774,884,911,1038,1102,1240,1292,1463,1530,1715,1861,2002 %N A320348 Number of partition into distinct parts (a_1, a_2, ... , a_m) (a_1 > a_2 > ... > a_m and Sum_{k=1..m} a_k = n) such that a1 - a2, a2 - a_3, ... , a_{m-1} - a_m, a_m are different. %C A320348 Also the number of integer partitions of n whose parts cover an initial interval of positive integers with distinct multiplicities. Also the number of integer partitions of n whose multiplicities cover an initial interval of positive integers and are distinct (see A048767 for a bijection). - _Gus Wiseman_, May 04 2019 %H A320348 Fausto A. C. Cariboni, <a href="/A320348/b320348.txt">Table of n, a(n) for n = 1..500</a> (terms 1..100 from Seiichi Manyama) %H A320348 Gus Wiseman, <a href="/A325325/a325325.txt">Sequences counting and ranking integer partitions by the differences of their successive parts.</a> %e A320348 n = 9 %e A320348 [9] ********* a_1 = 9. %e A320348 ooooooooo %e A320348 ------------------------------------ %e A320348 [8, 1] * a_2 = 1. %e A320348 *******o a_1 - a_2 = 7. %e A320348 oooooooo %e A320348 ------------------------------------ %e A320348 [7, 2] ** a_2 = 2. %e A320348 *****oo a_1 - a_2 = 5. %e A320348 ooooooo %e A320348 ------------------------------------ %e A320348 [5, 4] **** a_2 = 4. %e A320348 *oooo a_1 - a_2 = 1. %e A320348 ooooo %e A320348 ------------------------------------ %e A320348 a(9) = 4. %e A320348 From _Gus Wiseman_, May 04 2019: (Start) %e A320348 The a(1) = 1 through a(11) = 9 strict partitions with distinct differences (where the last part is taken to be 0) are the following (A = 10, B = 11). The Heinz numbers of these partitions are given by A325388. %e A320348 (1) (2) (3) (4) (5) (6) (7) (8) (9) (A) (B) %e A320348 (31) (32) (51) (43) (53) (54) (64) (65) %e A320348 (41) (52) (62) (72) (73) (74) %e A320348 (61) (71) (81) (82) (83) %e A320348 (91) (92) %e A320348 (631) (A1) %e A320348 (632) %e A320348 (641) %e A320348 (731) %e A320348 The a(1) = 1 through a(10) = 6 partitions covering an initial interval of positive integers with distinct multiplicities are the following. The Heinz numbers of these partitions are given by A325326. %e A320348 1 11 111 211 221 21111 2221 22211 22221 222211 %e A320348 1111 2111 111111 22111 221111 2211111 322111 %e A320348 11111 211111 2111111 21111111 2221111 %e A320348 1111111 11111111 111111111 22111111 %e A320348 211111111 %e A320348 1111111111 %e A320348 The a(1) = 1 through a(10) = 6 partitions whose multiplicities cover an initial interval of positive integers and are distinct are the following (A = 10). The Heinz numbers of these partitions are given by A325337. %e A320348 (1) (2) (3) (4) (5) (6) (7) (8) (9) (A) %e A320348 (211) (221) (411) (322) (332) (441) (433) %e A320348 (311) (331) (422) (522) (442) %e A320348 (511) (611) (711) (622) %e A320348 (811) %e A320348 (322111) %e A320348 (End) %t A320348 Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&UnsameQ@@Differences[Append[#,0]]&]],{n,30}] (* _Gus Wiseman_, May 04 2019 *) %Y A320348 Cf. A000009, A320347. %Y A320348 Cf. A007294, A007862, A048767, A098859, A179269, A320509, A320510, A325324, A325325, A325349, A325367, A325404, A325468. %K A320348 nonn %O A320348 1,4 %A A320348 _Seiichi Manyama_, Oct 11 2018