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Numbers m such that m^2 + p^2 = k^2, with p > 0, where p = A007954(m) = the product of digits of m.
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%I #16 Jul 17 2021 04:29:36

%S 429,437,598,1938,3584,3875,5576,6864,16758,36828,43778,47775,47859,

%T 56637,56672,82928,91798,129584,156782,165688,165838,178857,215985,

%U 379488,655578,798847,1881576,2893337,3918768,4816872,5439798,5829795,7558299,9675288,11943887

%N Numbers m such that m^2 + p^2 = k^2, with p > 0, where p = A007954(m) = the product of digits of m.

%H Giovanni Resta, <a href="/A334558/b334558.txt">Table of n, a(n) for n = 1..147</a> (terms < 2*10^13)

%e 429 is a term as p = 4*2*9 = 72 and 429^2 + 72^2 = 189225 = 435^2.

%e 16758 is a term as p = 1*6*7*5*8 = 1680 and 16758^2 + 1680^2 = 283652964 = 16842^2.

%o (PARI) isok(m) = my(p=vecprod(digits(m))); p && issquare(m^2 + p^2); \\ _Michel Marcus_, May 06 2020

%Y Cf. A007954, A000404, A078134, A334542, A334557.

%K nonn,base

%O 1,1

%A _Scott R. Shannon_, May 06 2020