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 A108655 Primes that are sums of the squares of two semiprimes. 1
 97, 181, 241, 277, 421, 457, 541, 641, 661, 709, 757, 821, 1109, 1117, 1237, 1301, 1381, 1597, 1621, 1669, 1709, 1901, 2069, 2341, 2381, 2417, 2437, 2557, 2617, 2677, 2741, 2797, 3041, 3061, 3221, 3557, 3637, 3701, 3733, 3989, 4241, 4261, 4421, 4517 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A002144. a(n) = A074985(i) + A074985(j) for appropriate i and j. LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE A000040(733) = 5557 = 81 + 5476 = (3*3)^2 + (2*37)^2 = A001358(3)^2 + A001358(25)^2 = A074985(3) + A074985(25), therefore 5557 is a term. PROG (Haskell) a108655 n = a108655_list !! (n-1) a108655_list = filter f a000040_list where    f p = any (> 0) \$ map (a064911 . a037213 . (p -)) \$                          takeWhile (< p) a074985_list -- Reinhard Zumkeller, Aug 09 2012 CROSSREFS Cf. A000404, A001358, A000290. Sequence in context: A261376 A142094 A142212 * A107193 A256775 A142398 Adjacent sequences:  A108652 A108653 A108654 * A108656 A108657 A108658 KEYWORD nonn AUTHOR Reinhard Zumkeller, Jul 07 2005 STATUS approved

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Last modified October 15 12:31 EDT 2019. Contains 328026 sequences. (Running on oeis4.)