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A325503
Heinz number of row n of the triangle of Stirling numbers of the second kind A008277.
2
2, 4, 20, 884, 528844, 3460086044, 340672148731996, 477782556719729075524, 11694209380474301218263758996, 4967476846044415922850025924897606724, 43298471669920632729336800855543564573041217668, 7790810575556906457316064931238939360882160372451591124244
OFFSET
1,1
COMMENTS
The Heinz number of a positive integer sequence (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
FORMULA
a(n) = Product_{i = 1..n} prime(A008277(n,i)).
A061395(a(n)) = A002870(n).
A056239(a(n)) = A000110(n).
EXAMPLE
The sequence of terms together with their prime indices begins:
2: {1}
4: {1,1}
20: {1,1,3}
884: {1,1,6,7}
528844: {1,1,10,15,25}
3460086044: {1,1,15,31,65,90}
340672148731996: {1,1,21,63,140,301,350}
477782556719729075524: {1,1,28,127,266,966,1050,1701}
11694209380474301218263758996: {1,1,36,255,462,2646,3025,6951,7770}
MATHEMATICA
Times@@@Table[Prime[StirlingS2[n, k]], {n, 1, 10}, {k, 1, n}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 07 2019
STATUS
approved