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A129546
Numbers n such that T(n)+10 is the next prime after T(n), where T(n) = A000217(n).
1
58, 61, 98, 138, 193, 217, 222, 233, 253, 266, 338, 358, 373, 393, 398, 402, 453, 461, 466, 477, 481, 542, 553, 557, 586, 597, 602, 618, 633, 646, 662, 761, 822, 838, 853, 857, 877, 898, 901, 913, 918, 926, 941, 986, 1006, 1041, 1061, 1077, 1126, 1157, 1161
OFFSET
1,1
LINKS
EXAMPLE
T(58)=1711 and 1711+10=1721 is the least prime > 1711;
T(61)=1891 and 1891+10=1901 is the least prime > 1891.
MATHEMATICA
nptQ[n_]:=Module[{tr=(n(n+1))/2}, NextPrime[tr]-tr==10]; Select[ Range[ 1200], nptQ] (* Harvey P. Dale, Dec 19 2017 *)
PROG
(PARI) isok(n) = t = n*(n+1)/2; nextprime(t+1) == (t + 10); \\ Michel Marcus, Oct 13 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, May 30 2007
STATUS
approved