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A325135
Size of the integer partition with Heinz number n after its inner lining, or, equivalently, its largest hook, is removed.
8
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 2, 0, 2, 0, 0, 1, 0, 0, 1, 0, 2, 1, 0, 0, 1, 0, 0, 1, 0, 0, 2, 0, 0, 0, 3, 2, 1, 0, 0, 2, 2, 0, 1, 0, 0, 1, 0, 0, 2, 0, 2, 1, 0, 0, 1, 2, 0, 1, 0, 0, 3, 0, 3, 1, 0, 0, 3, 0, 0, 1, 2, 0, 1, 0, 0, 2, 3, 0, 1, 0, 2, 0, 0, 3, 2, 2, 0, 1, 0, 0, 3
OFFSET
1,25
COMMENTS
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
FORMULA
a(n) = A056239(A325133(n)).
For n > 1:
a(n) = A056239(n) - A001222(n) - A061395(n) + 1.
a(n) = A056239(n) - A252464(n).
a(n) = A056239(n) - A325134(n) + 1.
EXAMPLE
The partition with Heinz number 715 is (6,5,3), with diagram
o o o o o o
o o o o o
o o o
which has inner lining
o o
o o o
o o o
or largest hook
o o o o o o
o
o
both of which have complement
o o o o
o o
which has size 6, so a(715) = 6.
MATHEMATICA
Table[If[n==1, 0, Total[Most[Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]-1]], {n, 100}]
PROG
(PARI)
A056239(n) = { my(f); if(1==n, 0, f=factor(n); sum(i=1, #f~, f[i, 2] * primepi(f[i, 1]))); }
A061395(n) = if(1==n, 0, primepi(vecmax(factor(n)[, 1])));
A325135(n) = if(1==n, 0, (1+A056239(n)-bigomega(n)-A061395(n))); \\ Antti Karttunen, Apr 14 2019
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 02 2019
EXTENSIONS
More terms from Antti Karttunen, Apr 14 2019
STATUS
approved