Numbers whose binary and ternary digit sums are prime: Difference between revisions

=={{header|AWK}}==

<lang AWK>

# syntax: GAWK -f NUMBERS_WHICH_BINARY_AND_TERNARY_DIGIT_SUM_ARE_PRIME.AWK

# converted from C

BEGIN {

start = 0

stop = 199

for (i=start; i<=stop; i++) {

if (is_prime(sum_digits(i,2)) && is_prime(sum_digits(i,3))) {

printf("%4d%1s",i,++count%10?"":"\n")

}

}

printf("\nBinary and ternary digit sums are both prime %d-%d: %d\n",start,stop,count)

exit(0)

}

function sum_digits(n,base, sum) {

do {

sum += n % base

} while (n = int(n/base))

return(sum)

}

function is_prime(x, i) {

if (x <= 1) {

return(0)

}

for (i=2; i<=int(sqrt(x)); i++) {

if (x % i == 0) {

return(0)

}

}

return(1)

}

</lang>

{{out}}

<pre>

5 6 7 10 11 12 13 17 18 19

21 25 28 31 33 35 36 37 41 47

49 55 59 61 65 67 69 73 79 82

84 87 91 93 97 103 107 109 115 117

121 127 129 131 133 137 143 145 151 155

157 162 167 171 173 179 181 185 191 193

199

Binary and ternary digit sums are both prime 0-199: 61

</pre>