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 A117725 Zeroless numbers for which the sum of the digits and the product of the digits are both Fibonacci numbers. 1
 1, 2, 3, 5, 8, 11, 12, 21, 111, 113, 131, 311, 1112, 1115, 1121, 1124, 1142, 1151, 1211, 1214, 1241, 1412, 1421, 1511, 2111, 2114, 2141, 2411, 4112, 4121, 4211, 5111, 11111, 11137, 11173, 11222, 11289, 11298, 11317, 11371, 11713, 11731, 11829, 11892, 11928 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Alois P. Heinz, Table of n, a(n) for n = 1..10000 David A. Corneth, PARI program EXAMPLE 18192 is a term because the sum of its digits is 1+8+1+9+2 = 21, the product of its digits is 1*8*1*9*2 = 144 and both 21 and 144 are Fibonacci numbers. MATHEMATICA isFibonacci[x_]:=MemberQ[Array[Fibonacci, 2x], x]; DeleteCases[ParallelTable[If[And[isFibonacci[Times@@IntegerDigits[n]], isFibonacci[Total[IntegerDigits[n]]]], n, a], {n, 1, 15000}], a] (* J.W.L. (Jan) Eerland, Jan 03 2024 *) PROG (PARI) isfib(n) = my(k=n^2); k+=(k+1)<<2; issquare(k) || issquare(k-8); \\ A000045 isok(k) = my(d=digits(k)); vecmin(d) && isfib(vecsum(d)) && isfib(vecprod(d)); \\ Michel Marcus, Jan 03 2024 (PARI) \\ See PARI program in links CROSSREFS Cf. A000045, A117774. Subsequence of A028840, A028890 and of A052382. Sequence in context: A070223 A298120 A298205 * A106637 A246361 A228855 Adjacent sequences: A117722 A117723 A117724 * A117726 A117727 A117728 KEYWORD base,nonn AUTHOR Luc Stevens (lms022(AT)yahoo.com), Apr 13 2006 EXTENSIONS a(45) from J.W.L. (Jan) Eerland, Jan 03 2024 Name clarified by Michel Marcus, Jan 03 2024 STATUS approved

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Last modified June 19 09:37 EDT 2024. Contains 373501 sequences. (Running on oeis4.)