A110554 Column 11 of table A105552.
56, 285, 954, 2366, 4711, 7936, 11712, 15448, 18450, 20155, 20329, 19078, 16746, 13780, 10644, 7712, 5235, 3325, 1970, 1081, 544, 247, 99, 33, 8, 1
Offset: 1
Examples
a(6) = A107601(6) = 7936.
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a(6) = A107601(6) = 7936.
The array begins 1 2 4 7 1 11 5 16 14 2 22 30 12 29 55 39 5 37 91 95 32 1
a(1) = 2 because 4+4+4 and 3+3+3+3 cannot be permuted. a(2) = 41 because there are 3 + 7 + 12 + 9 + 10 ways of permuting the associated partitions. 5553 (3 ways), 4441 & 544 (4+3 ways), 4432 (12 ways), 33331 & 4333 (5 + 4 ways) and 33322 (in 10 ways).
LinearRecurrence[{9,-36,84,-126,126,-84,36,-9,1},{2,41,292,1283,4253,11712,28261,61738,124763},30] (* Harvey P. Dale, Aug 21 2024 *)
The associated sequences begin for n = 15 through 19: ........................1.......5 ........................3.......18 ................3.......18......60 ........3.......18......60......150 1.......7.......25......65......140 ........................6.......42 ................12......84......324 ........12......84......324.....924 ........6.......42......162.....462 4.......32......132.....392.....952 ........................10......80 ................30......240.....1050 ........10......90......420.....1400 ........30......240.....1050....3360 1.......11......56......196.....546 ........................15......135 ................60......540.....2640 ........15......165.....900.....3420 ........................21......210 ................35......385.....2205 ........................28......308 ........................1.......19 therefore this sequence begins 6 126 992 4921 18450
The associated partitions begin (for n = 14, 15, 16, ... ................1.......5.......14 ................3.......18......60 ........3.......18......60......150 3.......18......60......150.....315 ................6.......42......162 ........12......84......324.....924 4.......32......132.....392.....952 6.......42......162.....462.....1092 ................10......80......350 ........30......240.....1050....3360 5.......50......245.....840.....2310 ................15......135.....660 ........20......200.....1040....3840 ................21......210.....1134 ................1.......17......125 therefore this sequence begins 18 207 1198 4825 15448 ...
The column sums begin 1 2 4 10 26 72 202 580 ... because the structure of the Array begin as follows: 1.................................................................. ......1............................................................ ......1............................................................ ............1...................................................... ............2......2............................................... ............1...................................................... ..................1................................................ ..................3......5......3.................................. ..................3......5......3.................................. ..................1................................................ ............................1...................................... ............................4.......9.......9.......4.............. ............................6.......16......22......16.......6..... ............................4.......9.......9.......4.............. ............................1...................................... etc.
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