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A357896
Additive triprimes.
0
8, 44, 66, 75, 99, 116, 125, 138, 147, 165, 170, 174, 242, 246, 255, 273, 279, 282, 318, 332, 345, 354, 363, 369, 387, 404, 426, 435, 477, 507, 530, 534, 549, 561, 578, 596, 602, 606, 615, 639, 642, 651, 657, 668, 705, 710, 741, 747, 822, 873, 903, 909, 927, 938, 956, 963, 981, 1025, 1034, 1038, 1052, 1065, 1070, 1074
OFFSET
1,1
COMMENTS
Triprimes for which the sum of the digits is also a triprime.
EXAMPLE
75 = 3*5*5 and 5 + 7 = 12 = 2*2*3 (both are product of 3 primes).
MATHEMATICA
s = Select[Range[8, 1500], 3 == PrimeOmega[#] &]; s = Select[s, 3 == PrimeOmega[Total[IntegerDigits[#]]] &]
PROG
(PARI) istp(k) = bigomega(k)==3; \\ A014612
isok(k) = istp(k) && istp(sumdigits(k)); \\ Michel Marcus, Nov 02 2022
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Oct 18 2022
STATUS
approved