A334557 -id:A334557 - cp's OEIS frontend

A334542 Numbers m such that m^2 = p^2 + k^2, with p > 0, where p = A007954(m) = the product of digits of m.

1, 2, 3, 4, 5, 6, 7, 8, 9, 58, 85, 375, 666, 1968, 1998, 3578, 3665, 3891, 4658, 4995, 6675, 7735, 18434, 27475, 28784, 46692, 56763, 58896, 59577, 59949, 76965, 186633, 186673, 795848, 949968, 965667, 1339575, 1587616, 1929798, 2765388, 2989584, 3674195, 4763568, 5762784, 36741656, 58988961, 134369685, 188959392

Offset: 1

Scott R. Shannon, May 05 2020

			58 is a term as p = 5*8 = 40 and 58^2 = 3364 = 40^2 + 42^2.
3891 is a term as p = 3*8*9*1 = 216 and 3891^2 = 15139881 = 216^2 + 3885^2.

Giovanni Resta, Table of n, a(n) for n = 1..140 (terms < 2*10^13)

Cf. A007954, A000404, A078134, A334557, A334558.

Subsequence of A052382 (zeroless numbers).

isok(m) = my(p=vecprod(digits(m))); p && issquare(m^2 - p^2); \\ Michel Marcus, May 06 2020

A334558 Numbers m such that m^2 + p^2 = k^2, with p > 0, where p = A007954(m) = the product of digits of m.

Original entry on oeis.org

429, 437, 598, 1938, 3584, 3875, 5576, 6864, 16758, 36828, 43778, 47775, 47859, 56637, 56672, 82928, 91798, 129584, 156782, 165688, 165838, 178857, 215985, 379488, 655578, 798847, 1881576, 2893337, 3918768, 4816872, 5439798, 5829795, 7558299, 9675288, 11943887

Offset: 1

Scott R. Shannon, May 06 2020

			429 is a term as p = 4*2*9 = 72 and 429^2 + 72^2 = 189225 = 435^2.
16758 is a term as p = 1*6*7*5*8 = 1680 and 16758^2 + 1680^2 = 283652964 = 16842^2.

Giovanni Resta, Table of n, a(n) for n = 1..147 (terms < 2*10^13)

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

isok(m) = my(p=vecprod(digits(m))); p && issquare(m^2 + p^2); \\ Michel Marcus, May 06 2020

cp's OEIS Frontend

A334542 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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