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A067694
Minimum number of distinct parts in a self-conjugate partition of n, or 0 if n=2.
2
0, 1, 0, 2, 1, 2, 3, 2, 2, 1, 3, 2, 2, 2, 3, 2, 1, 2, 3, 2, 2, 2, 3, 2, 2, 1, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 1, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 1, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 1, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 1, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 1, 2, 3
OFFSET
0,4
COMMENTS
There are no self-conjugate partitions of 2, so we set a(2)=0.
LINKS
FORMULA
a(0)=a(2)=0; a(n^2)=1; a(4n+2)=3 for n>0; a(n)=2 in all other cases.
MATHEMATICA
a[0]=a[2]=0; a[n_] := Which[IntegerQ[Sqrt[n]], 1, Mod[n, 4]==2, 3, True, 2]
PROG
(PARI) A067694(n) = if((2==n)||!n, 0, if(2==(n%4), 3, if(issquare(n), 1, 2))); \\ Antti Karttunen, Sep 27 2018
CROSSREFS
Sequence in context: A178412 A182598 A331084 * A131810 A365143 A233519
KEYWORD
easy,nonn
AUTHOR
Naohiro Nomoto, Feb 05 2002
EXTENSIONS
Edited by Dean Hickerson, Feb 15 2002
STATUS
approved