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 A179653 Triangular numbers (A000217) which are also primes in carryless digital root arithmetic in base 10 (A169911). 0
 3, 6, 10, 15, 21, 28, 45, 55, 78, 91, 105, 136, 406, 496, 528, 595, 703, 741, 1035, 1081, 1225 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The complement, triangular numbers (A000217) which are not primes in carryless digital root arithmetic in base 10 (A169911), begins {1, 36, 66, 153, 171, 190, 210, 231, 253, 276, 300, 325, 351, 378, 435, 465, ...}. LINKS FORMULA A000217 INTERSECTION A169911. EXAMPLE 1, though triangular, is a unit, not a prime, in standard or carryless arithmetic. 36 is triangular, A000217(8), yet not in A169911 since in carryless digital root arithmetic in base 10 we have 3*15 = 36 where both 3 and 15 are primes, and 3*18=36. Similarly, 66 is triangular, A000217(11), yet not in A169911. CROSSREFS Cf. A000217, A169911, Sequence in context: A025706 A025730 A066353 * A117520 A147846 A062099 Adjacent sequences:  A179650 A179651 A179652 * A179654 A179655 A179656 KEYWORD nonn,less,base,more AUTHOR Jonathan Vos Post, Jul 22 2010 STATUS approved

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Last modified September 20 16:50 EDT 2021. Contains 347586 sequences. (Running on oeis4.)