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A135548 Numbers in A134651 which are the sum of two terms from A001043 in a unique way. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..58.

EXAMPLE

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.

PROG

(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

CROSSREFS

Cf. A001043, A134651, A135045.

Sequence in context: A219110 A226024 A134651 * A102502 A153045 A055984

Adjacent sequences:  A135545 A135546 A135547 * A135549 A135550 A135551

KEYWORD

nonn

AUTHOR

Zak Seidov, Feb 15 2008

EXTENSIONS

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

STATUS

approved

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Last modified April 20 03:36 EDT 2019. Contains 322294 sequences. (Running on oeis4.)