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Revision History for A351004 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

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Alternately constant partitions. Number of integer partitions y of n such that y_i = y_{i+1} for all odd i.
(history; published version)
#10 by Susanna Cuyler at Sun Feb 06 23:10:28 EST 2022
STATUS

proposed

approved

#9 by Gus Wiseman at Fri Feb 04 00:52:58 EST 2022
STATUS

editing

proposed

#8 by Gus Wiseman at Fri Feb 04 00:52:55 EST 2022
CROSSREFS

The version for even instead of odd positions indices is A351003, even-length A351012.

#7 by Gus Wiseman at Thu Feb 03 20:28:59 EST 2022
CROSSREFS

The version for even instead of odd positions is A351003, even-length A351012.

STATUS

proposed

editing

#6 by Gus Wiseman at Mon Jan 31 20:52:09 EST 2022
STATUS

editing

proposed

#5 by Gus Wiseman at Mon Jan 31 20:52:05 EST 2022
COMMENTS

Partitions These are partitions of n with all even multiplicities (or run-lengths), except possibly the last.

CROSSREFS

The version for alternately distinct unequal instead of equal parts is A122129, even-length A351008.

The opposite version for alternately distinct parts is A122135, even-length A122134 instead of odd positions is A351003.

The even instead of odd version is A351003.

Cf. A000070, A018819, A027383, 1A088218, A088218, A067661, A101417, `A305148, ~A339846, `A350837, `A350839, A122134, A122135, A350842, `A350844, ~A350948, A351007.

#4 by Gus Wiseman at Mon Jan 31 20:42:25 EST 2022
COMMENTS

Also the number of integer partitions Partitions of n with all even multiplicities (or run-lengths) , except possibly the last, first A096441, both A349060.

#3 by Gus Wiseman at Mon Jan 31 20:39:23 EST 2022
NAME

Alternately constant partitions. Number of integer partitions y of n such that y_i = y_{i+1} for all odd i.

#2 by Gus Wiseman at Mon Jan 31 15:00:11 EST 2022
NAME

allocated Number of integer partitions y of n such that y_i = y_{i+1} for Gus Wisemanall odd i.

DATA

1, 1, 2, 2, 3, 3, 5, 4, 7, 7, 10, 9, 15, 13, 21, 19, 28, 26, 40, 35, 54, 49, 72, 64, 97, 87, 128, 115, 167, 151, 220, 195, 284, 256, 366, 328, 469, 421, 598, 537, 757, 682, 959, 859, 1204, 1085, 1507, 1354, 1880, 1694, 2338, 2104, 2892, 2609, 3574, 3218, 4394

OFFSET

0,3

COMMENTS

Also the number of integer partitions of n with all even multiplicities (or run-lengths) except possibly the last, first A096441, both A349060.

EXAMPLE

The a(1) = 1 through a(9) = 7 partitions:

1 2 3 4 5 6 7 8 9

11 111 22 221 33 331 44 333

1111 11111 222 22111 332 441

2211 1111111 2222 22221

111111 3311 33111

221111 2211111

11111111 111111111

MATHEMATICA

Table[Length[Select[IntegerPartitions[n], And@@Table[#[[i]]==#[[i+1]], {i, 1, Length[#]-1, 2}]&]], {n, 0, 30}]

CROSSREFS

The ordered version (compositions) is A016116.

The even-length case is A035363.

A reverse version is A096441, both A349060.

The version for alternately distinct instead of equal parts is A122129, even-length A351008.

The opposite version for alternately distinct parts is A122135, even-length A122134.

The even instead of odd version is A351003.

The strict version is A351005, opposite A351006, even-length A035457.

Cf. A000070, A018819, A027383, 1A088218, A067661, A101417, `A305148, ~A339846, `A350837, `A350839, A350842, `A350844, ~A350948, A351007.

KEYWORD

allocated

nonn

AUTHOR

Gus Wiseman, Jan 31 2022

STATUS

approved

editing

#1 by Gus Wiseman at Fri Jan 28 23:12:07 EST 2022
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved