The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A156322 Integers n such that if you insert between each of their digits either "*" (times), "^" (exponentiation), or "nothing" (so that two or more digits are merged to form an integer), then you can recover n in a nontrivial way (however, two "^" mustn't be adjacent - you must avoid decompositions containing a^b^c). 2
 2592, 34425, 35721, 312325, 344250, 357210, 492205, 1492992, 1729665, 1769472, 3123250, 3365793, 3442500, 3472875, 3572100, 3639168, 4922050, 6718464, 6967296, 7587328, 10744475, 10756480, 13745725, 13942125, 14569245, 16746975, 17266392, 17296650, 17577728, 17694720 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The number of terms in the sequence is infinite, because there are numbers like 34425 = 3^4*425, 344250 = 3^4*4250, 3442500 = 3^4*42500, etc. LINKS Jean-Marc Falcoz, Illustration EXAMPLE 2592 = 2^5 * 9^2      34425 = 3^4 * 425      35721 = 3^5 * 7 * 21     312325 = 31^2 * 325     344250 = 3^4 * 4250     357210 = 3^5 * 7 * 210     492205 = 49^2 * 205    1492992 = 1 * 4 * 9 * 2^9 * 9^2    1729665 = 17^2 * 9 * 665    1769472 = 1^7 * 6 * 9 * 4^7 * 2    3123250 = 31^2 * 3250    3365793 = 3*3^6 * 57 * 9 * 3    3442500 = 3^4 * 42500    3472875 = 3^4 * 7^2 * 875    3572100 = 3^5 * 7 * 2100    3639168 = 3^6 * 39 * 16 * 8    4922050 = 49^2 * 2050    6718464 = 6^7 * 1^84 * 6 * 4    6967296 = 6 * 9 * 6 * 7 * 2^9 * 6    7587328 = 7 * 58 * 73 * 2^8   10744475 = 1^0 * 7^4 * 4475   10756480 = 10 * 7^5 * 64 * 8^0   13745725 = 1^3 * 7^4 * 5725   13942125 = 1^3 * 9^4 * 2125   14569245 = 1^4 * 569^2 * 45   16746975 = 1^6 * 7^4 * 6975   17266392 = 172 * 66 * 39^2   17296650 = 17^2 * 9 * 6650   17577728 = 17 * 577 * 7 * 2^8   17694720 = 1^7 * 6 * 9 * 4^7 * 20. ------------------------------ 3^5 * 1482 * 9760 = 3514829760 is the only pandigital with this property. - Jean-Marc Falcoz, Mar 19 2009 ----------------------------- 17 * 577 * 7 * 2^8 = 17577728 1297 * 7^3 * 31 * 941 = 12977331941 are the only composite integers up to 10^11 that are printer's errors with decomposition in prime factors. - Jean-Marc Falcoz, Sep 09 2018 CROSSREFS Two other versions of the "printer's errors" sequence are A096298 and A116890. This one is harder to compute because it's more general; you can have decompositions like ab*c*def^g*h*ij. Sequence in context: A179702 A258728 A326747 * A096298 A204782 A204775 Adjacent sequences:  A156319 A156320 A156321 * A156323 A156324 A156325 KEYWORD base,nonn AUTHOR Jean-Marc Falcoz, Feb 08 2009, Feb 14 2009 EXTENSIONS Edited by N. J. A. Sloane, Feb 22 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 13 04:09 EDT 2021. Contains 343836 sequences. (Running on oeis4.)