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 A108662 Numbers whose sum of squares of digits is a prime. 7
 11, 12, 14, 16, 21, 23, 25, 27, 32, 38, 41, 45, 49, 52, 54, 56, 58, 61, 65, 72, 78, 83, 85, 87, 94, 101, 102, 104, 106, 110, 111, 113, 119, 120, 126, 131, 133, 137, 140, 146, 159, 160, 162, 164, 166, 168, 173, 179, 186, 191, 195, 197, 199, 201, 203, 205, 207, 210 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS If m is in the sequence, then so are 10*m and any anagram (even with adding zeros between digits) of m. E.g., 12 is a term, hence 21, 102, 120, 201, 10020 all are here. A sequence of primitive terms is of interest. It starts with 11, 12, 14, 16, 23, 25, 27, 38, 45, 49, 56, 58, 78, 111, 113, 119, 126, 133, 137, 146, 159, 166, 168, 179, 199. Note that digits are in nondecreasing order. - Zak Seidov, Dec 31 2013 LINKS Harvey Dale and Zak Seidov, Table of n, a(n) for n = 1..10000 [First 1000 terms from Harvey Dale] EXAMPLE 23 is in the sequence because 2^2 + 3^2 = 13 is a prime. MATHEMATICA Select[Range[300], PrimeQ[Total[IntegerDigits[#]^2]]&] (* Harvey P. Dale, May 25 2012 *) PROG (PARI) isok(n) = isprime(norml2(digits(n))); \\ Michel Marcus, Jan 09 2019 CROSSREFS Cf. A003132, A009994, A052034, A234021. Sequence in context: A221699 A227823 A140353 * A210767 A182404 A234021 Adjacent sequences:  A108659 A108660 A108661 * A108663 A108664 A108665 KEYWORD nonn,base AUTHOR Zak Seidov, Jun 16 2005 STATUS approved

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Last modified October 22 05:29 EDT 2019. Contains 328315 sequences. (Running on oeis4.)