A135548 Numbers in A134651 which are the sum of two terms from A001043 in a unique way.

10, 13, 16, 17, 20, 23, 24, 26, 29, 30, 32, 35, 38, 41, 44, 47, 50, 57, 64, 65, 68, 70, 73, 80, 82, 83, 88, 89, 94, 95, 105, 110, 117, 118, 125, 133, 140, 143, 148, 149, 154, 157, 167, 176, 177, 178, 182, 191, 192, 200, 203, 208, 209, 215, 221, 227, 236, 242

Offset: 1

Author

Zak Seidov, Feb 15 2008

Keywords

• nonn

Comments

Numbers that are the sum of two terms of A001043, but not sum of a different pair of two terms.

Examples

			Recall that A001043 begins with 5,8,12,18,24,30,36,42,52,60,68,78,84,90, ...
So 48 is not in the sequence because 48 = 18+30 = 24+24.
But 88 is in the sequence as it is only = 52+36.
And 89 is there too because = 84+5.
		

Crossrefs

Cf. A001043, A134651, A135045.

Programs

PARI

issum(i, vss) = {nb = 0; for (j = 1, #vss, if (vss[j] > i, break); for (k = 1, j, sv = vss[j] + vss[k]; if (sv == i, nb++); if (sv > i, break););); return (nb == 1);}
lista(nn) = {vec = vector(nn, i, i); vss = select(i->((precprime((i-1)/2) + nextprime(i/2) == i) && (i>2)), vec); for (i = 1, nn, if (issum(i, vss), print1(i, ", ")););} \\ Michel Marcus, Oct 14 2013

Extensions

Example, corrected and extended by Michel Marcus, Oct 14 2013