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 A334557 Numbers m such that m = p^2 + k^2, with p > 0, where p = A007954(m) = the product of digits of m. 3
 1, 13, 41, 61, 125, 212, 281, 613, 1156, 1424, 2225, 3232, 3316, 4113, 11125, 11281, 11525, 12816, 14913, 16317, 16441, 19125, 21284, 21625, 24128, 25216, 27521, 31525, 53125, 56116, 61321, 65161, 71325, 82116, 82217, 83521, 84313, 111812, 113125, 113625, 115336, 115681, 117125, 118372 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Giovanni Resta, Table of n, a(n) for n = 1..10000 EXAMPLE 13 is a term as p = 1*3 = 3 and 13 = 3^2 + 2^2. 281 is a term as p = 2*8*1 = 16 and 281 = 16^2 + 5^2. 118372 is a term as p = 1*1*8*3*7*2 = 336 and 118372 = 336^2 + 74^2. PROG (PARI) isok(m) = my(p=vecprod(digits(m))); p && issquare(m - p^2); \\ Michel Marcus, May 06 2020 CROSSREFS Cf. A007954, A000404, A078134, A334542, A334558. Sequence in context: A337146 A122730 A101167 * A146238 A039339 A031373 Adjacent sequences: A334554 A334555 A334556 * A334558 A334559 A334560 KEYWORD nonn,base AUTHOR Scott R. Shannon, May 06 2020 STATUS approved

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Last modified December 5 04:26 EST 2023. Contains 367571 sequences. (Running on oeis4.)