OFFSET
2,5
COMMENTS
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
LINKS
FORMULA
a(n) = a(A005117(n)). - David A. Corneth, Sep 06 2018
EXAMPLE
63 is the Heinz number of (4,2,2), which has LCM 4 and GCD 2, so a(63) = 4/2 = 2.
91 is the Heinz number of (6,4), which has LCM 12 and GCD 2, so a(91) = 12/2 = 6.
MATHEMATICA
Table[With[{pms=Cases[FactorInteger[n], {p_, k_}:>PrimePi[p]]}, LCM@@pms/GCD@@pms], {n, 2, 100}]
PROG
(PARI) A316431(n) = if(1==n, 1, my(pis = apply(p -> primepi(p), factor(n)[, 1]~)); lcm(pis)/gcd(pis)); \\ Antti Karttunen, Sep 06 2018
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Gus Wiseman, Jul 02 2018
EXTENSIONS
More terms from Antti Karttunen, Sep 06 2018
STATUS
approved