#!/bin/perl
use Math::BigInt;

select((select(STDOUT), $| = 1)[0]);

#=======================================================================
my $zero = new Math::BigInt(0);
my $one = new Math::BigInt(1);
my $ten = new Math::BigInt(10);

#=======================================================================
my %h = (0, $one);
sub h {
	my ($n) = @_;
	return $h{$n} if $h{$n};
	my $s = $zero;
	my $t = $one;
	my ($x, $y) = ($n, 1);
	for (my ($x, $y) = ($n, 1); $x > 0;) {
		$t *= $x--, $t /= $y++;
		$s += $t*h($x);
	}
	return $h{$n} = $s;
}

sub fbase {
	my @p = @_;
	my @i = (0, (0) x @p);
	my $s = $zero;
# $s = grep($_ != 1, @p) ? $zero : $one;
	for (;;) {
		for (@i) { last if $_ = -1-$_; }
		last if $i[@p];
		@q = map($p[$_]+$i[$_], 0..$#p);
		my $c = eval join("*", -2, grep($_, @i));
		$s += $c*f(@q);
	}
	return $s;
}

sub f {
	my (@p) = (sort {$a <=> $b} grep($_, @_));
	return h(int(@p)) unless grep($_ != 1, @p);
	return 0 if $p[0] < 0;
	my $f = $f{"@p"};
	return $f ? $f : ($f{"@p"} = fbase(@p));
}

print f(@ARGV), "\n";