A084195 Even numbers n such that the sum of the digits is prime, n/2 is prime and the sum of the digits of n/2 is also prime.
14, 58, 94, 122, 166, 274, 278, 302, 346, 382, 386, 454, 458, 526, 562, 566, 634, 674, 706, 746, 818, 922, 926, 1114, 1154, 1198, 1202, 1282, 1286, 1466, 1514, 1594, 1642, 1646, 1774, 1822, 1954, 2038, 2078, 2102, 2182, 2186, 2218, 2258, 2326, 2362
Offset: 1
Examples
5+8=13 for n=58 and 2+9=11 for n/2=29=prime. 1+2+2=5 for n=122 and 6+1=7 for n/2=61=prime. 2+7+8=17 for n=278 and 1+3+9=13 for n/2=139=prime.
Crossrefs
Subsequence of A084194.
Programs
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PARI
isok(n) = {if (n % 2, return (0)); dn = digits(n); dh = digits(n/2); isprime(n/2) && isprime(sum(i=1, #dn, dn[i])) && isprime(sum(i=1, #dh, dh[i]));} \\ Michel Marcus, Aug 12 2013
Extensions
More terms from Michel Marcus, Aug 12 2013