freemarker if statement sequencing - logic

Question

I'm trying to write an #if statement with a sequence of numbers. Basically, if a certain field matches any of a subset of numbers (shown below with || or operators) then assign it as "bayarea", elseif a different subset, then a different name, etc. Is this possible without a bunch of nested "or" statements?
I'm getting a syntax error saying that it's expecting a boolean yes/no statement.
<#if TEST_CONTACTS_LIST.PREFERRED_STORE ==
{12||21||22||38||46||67||71||74||76||77||83||86||104||113||119||143>
{bayarea}
<#elseif TEST_CONTACTS_LIST.PREFERRED_STORE ==
{34||62||84||91||137||144||152||169}>
{blueridge}
<#elseif TEST_CONTACTS_LIST.PREFERRED_STORE ==
{18||44||49||50||61||68||121||182}>
{frontrange}
<#else>
</#if>

Answer 1

You don't need nesting:
<#if TEST_CONTACTS_LIST.PREFERRED_STORE == 12
|| TEST_CONTACTS_LIST.PREFERRED_STORE == 21 || ...>
Though that's surely too verbose, but you can do this:
<#assign store = TEST_CONTACTS_LIST.PREFERRED_STORE>
<#if store == 12 || store == 21 || ...>
But I think what you are looking for is this (or this combined with the #assign, if you have several #elseif-s):
<#if [12, 21, ...]?seq_contains(TEST_CONTACTS_LIST.PREFERRED_STORE)>
This is a possibility too (just don't forget the #break-s):
<#switch TEST_CONTACTS_LIST.PREFERRED_STORE>
<#case 12><#case 21>...
{bayarea}
<#break>
<#case 34><#case 62>...
{bluebridge}
<#break>
...
</#switch>

Answer 2

Those are four good answers above. To expand on it, I'd do something like this:
<#assign pref_store = TEST_CONTACTS_LIST.PREFERRED_STORE>
<#assign area = "">
<#assign group1 = [12,21,22,38,46,67,71,74,76,77,83,86,104,113,119,143]>
<#assign group2 = [34,62,84,91,137,144,152,169]>
<#assign group3 = [18,44,49,50,61,68,121,182]>
<#if group1?seq_contains(pref_store)>
<#assign area = "bayarea">
<#elseif group2?seq_contains(pref_store)>
<#assign area = "blueridge">
<#elseif group3?seq_contains(pref_store)>
<#assign area = "frontrange">
<#else>
<#assign area = "whatever">
</#if>
Your Preferred Store Area is ${area}.
Alternatively, instead of Sequences / Arrays, you could also set these values as a string.
For example:
<#assign pref_store = "${TEST_CONTACTS_LIST.PREFERRED_STORE}">
<#assign group1 = "12,21,22,38,46,67,71,74,76,77,83,86,104,113,119,143">
then the if statement would be the following:
<#if group1?contains(pref_store)>
(Notice the ?contains instead of ?seq_contains)
etc..