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 A085774 (n / sum of digits of n) and (n+1 / sum of digits of n+1) are both semiprime. 0
 80, 440, 735, 1014, 1160, 1274, 1547, 2023, 2820, 4806, 5490, 5565, 5875, 6137, 7215, 7748, 10309, 10520, 12104, 12255, 12256, 12257, 12614, 13112, 13481, 14120, 14415, 14705, 14927, 15317, 16434, 17118, 20174, 20175, 20538, 20604, 20804, 21307 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Note the quadruple: 12255,12256,12257,12258 and the triple: 20174,20175,20176. Conjecture: sequence is infinite. LINKS Table of n, a(n) for n=0..37. MATHEMATICA SequencePosition[Table[PrimeOmega[n/Total[IntegerDigits[n]]], {n, 22000}], {2, 2}][[;; , 1]] (* Harvey P. Dale, Mar 18 2023 *) CROSSREFS Sequence in context: A273292 A234333 A234326 * A233353 A233354 A200432 Adjacent sequences: A085771 A085772 A085773 * A085775 A085776 A085777 KEYWORD base,nonn AUTHOR Jason Earls, Jul 23 2003 STATUS approved

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Last modified June 8 07:54 EDT 2023. Contains 363157 sequences. (Running on oeis4.)